Physics and Astronomy

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This is the collection for the University of Waterloo's Department of Physics and Astronomy.

Research outputs are organized by type (eg. Master Thesis, Article, Conference Paper).

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Automated Tuning and Optimal Control of Spin Qubits in Quantum Dot Devices
(University of Waterloo, 2024-09-17) Paurevic, Andrija; Baugh, Jonathan
Silicon quantum dots present a promising foundation for realizing scalable quantum processors, leveraging the advantages of a mature semiconductor industry. Two significant challenges hinder their development: the laborious tuning of these devices and the coherent control of their spin qubits. This thesis presents contributions towards addressing these challenges by harnessing physics-informed machine learning. Tuning these devices involves navigating complex parameter spaces, plagued with variability and fabrication imperfections, to identify optimal operating conditions. This process demands extensive time and resources by a researcher to perform large amounts of data collection and analysis. My work takes steps towards on achieving fully autonomous tuning of these devices, with the automated formation of a single quantum dot. This work involves the application of data analysis and computer vision techniques to extract relevant features from data, guiding the tuning process in real-time. This tool allows single quantum dots to be formed autonomously, freeing researchers to focus on investigating the physics of the device. Progress in multi-dot systems was also made by developing a data segmentation model that successfully identifies and segments charge and dot configurations in charge stability diagram data. This enables rapid data analysis to determine optimal voltage settings for achieving the desired device state. Optimal control is crucial for guiding quantum systems through unitary operations while minimizing decoherence. Using a simulated open quantum system Hamiltonian for spin qubits, I developed a protocol to optimize experimental control signals, allowing for the implementation of unitary gate operations with arbitrary fidelity. The protocol designed experimental pulses for single-qubit rotations and entangling gates in a two-qubit system, achieving fidelities above the error correction threshold. Additionally, it utilizes modern machine learning frameworks, making it scalable to multi-qubit systems. The work presented in this thesis serves as an important foundation for future advancements in our research group.
Carbon nanotube electromechanical systems: Non-linear dynamics and self-oscillation
(University of Waterloo, 2020-05-13) Willick, Kyle; Baugh, Jonathan
This thesis is motivated by the many sensing applications of carbon nanotube (CNT) nano-electromechanical systems (NEMS), both previous state-of-the-art demonstrations and proposed new uses. This research is particularly focused on the long term goal of realizing the magnetic force sensing of molecular nanomagnets, proposed in reference [1]. The fabrication of micron long, small diameter, high quality suspended carbon nanotubes is a challenging task. Integrating ferromagnetic structures which are incompatible with the CNT growth procedures increases this challenge. In this thesis, devices suitable for magnetic force sensing experiments are realized by separating the chemical vapour deposition growth of CNTs from the device contacts and gates, while maintaining CNT quality. Using conventional readout techniques, the low-temperature measurement of the CNT NEMS mechanical state is usually limited by the CNT contact resistance and capacitance of the measurement cabling/circuit. I describe the use of a heterojunction bipolar transistor (HBT) amplifying circuit operating at cryogenic temperatures near the device to measure the mechanical amplitude at microsecond timescales. A Coulomb rectification scheme, in which the probe signal is at much lower frequency than the mechanical drive signal, allows investigation of the transient response with strongly non-linear driving. The transient dynamics in both the linear and non-linear regimes are measured and modeled by including Duffing and non-linear damping terms in a harmonic oscillator equation. The non-linear regime can result in faster sensing response times, on the order of 10 μs for the device and circuit presented. Self-driven oscillations in suspended carbon nanotubes can create apparent instabilities in the electrical conductance of the CNT. In literature, such instabilities have been observed in kondo regime or high bias transport. In this thesis, I observed self-driven oscillations which created significant conduction within the nominally Coulomb-blockaded low-bias transport. Using a master equation system model, these oscillations are shown to be the result of strongly energy dependent electron tunneling to the contacts of high quality CNT NEMS operated at sub-Kelvin temperatures. Finally, in a separate research project, I consider the noise characterization of spin qubits interacting with the environment. In particular, I address the problem of probing the spectral density S(ω) of semi-classical phase noise using a spin interacting with a continuous-wave (CW) resonant excitation field. Previous CW noise spectroscopy protocols have been based on the generalized Bloch equations (GBE) or the filter function formalism, and assumed weak coupling to a Markovian bath. However, those protocols can substantially underestimate S(ω) at low frequencies when the CW pulse amplitude becomes comparable to S(ω). I derive the coherence decay more generally by extending to higher orders in the noise strength and discarding the Markov approximation. Numerical simulations show that this provides a more accurate description of the spin dynamics compared to a simple exponential decay, especially on short timescales. Exploiting these results, a new protocol is developed that uses an experiment at a single CW pulse amplitude to extend the spectral range over which S(ω) can be reliably determined, down to ω=0.
Characterization of gate oxides and microwave resonators for silicon spin qubit devices
(University of Waterloo, 2022-01-21) Currie, Alex; Baugh, Jonathan
Silicon quantum dots present themselves as a promising implementation for quantum information processing due to the fact that they possess a small chip foot-print, yield high coherence times and are able to leverage the semiconductor industry. These nanoscopic devices rely on forming an electrostatic confinement for individual electrons. To accomplish this, an overlapping metallic gate geometry is implemented. The overlapping metallic gates are typically electrically isolated from one another by an insulating asher oxide layer. Due to unreliable processes during quantum dot fabrication, we substitute the asher oxide for a more robust and reliable oxide. For this, gate-oxide test structures are fabricated to simulate the overlapping gate geometry while various oxides are grown and deposited. It is found that oxides, grown by either ashing or hotplate in tandem with atomic layer deposited Al2O3, yield substantially higher breakdown voltages than conventional methods. One issue single electron spin qubits face is noise generated by charge traps. Charge traps appear at the Si/Oxide interface and seriously impedes many aspects of a quantum processor such as qubit coherence times, electrostatic screening effects and two-qubit gate fidelities. Here, we characterize the density of interface traps on a multitude of oxides found in the Quantum Nano-Fabrication and Characterization Facility. These oxides in clude plasma enhanced chemical vapour deposition (PECVD) SiO2, Tystar dry oxidation, commercial thermal SiO2, atomic layer deposition (ALD) Al2O3 and ALD HfO2. We find that each of these oxides is plagued by a high density of fixed charge and interface traps. We also implement forming gas anneals at high temperature to help passivate the charge traps. It is found that a forming gas anneal at 400C for 10 minutes reduces the number of interface traps by several orders of magnitude and that PECVD SiO2 and ALD Al2O3 host the smallest interface trap density of approximately 1010 eV−1 cm−2 . A major issue facing this implementation of quantum computing is the ability to scale up. Current methods of single qubit rotation are electron spin resonance and electron dipole spin resonance. In either method, a high frequency (HF) transmission line is placed nearby the quantum dots. For a large scale quantum computer, hundreds to thousands of transmission lines and therefore HF interconnects will be necessary, dramatically increasing the complexity of the device and reducing the qubit packing density. In this thesis, we present an elegant solution, dramatically reducing the need for many interconnects. A superconducting microresonator sits directly above the quantum processor providing an oscillatory magnetic field to perform single qubit rotations over an area of 1 mm2 . With a modest quantum dot pitch of 100 nm, approximately 40 million qubits can fit within this region. The resonator possess a unique shape to minimize the electric field component while maximizing the magnetic field ‘felt’ by the qubits. Electrons are tuned on and off of iv resonance by electrostatic tuning of the electron g-factor. We fabricate and characterize a prototype resonator’s transmission coefficient to determine its resonant frequency at room temperature and at 1.4K. Both measurements agree with simulations with a resonance frequency of approximately 16 GHz.
Development of III-V Semiconductor Surface Quantum Wells for Hybrid Superconducting Device Applications
(University of Waterloo, 2024-02-20) Bergeron, Emma; Baugh, Jonathan; Baugh, Jonathan
This thesis concerns the materials development of both InSb/InAlSb and InAs/AlGaSb surface quantum wells: Two of the most promising platforms for the study of proximity-induced superconductivity in semiconductors with strong spin-orbit interaction. Our work covers the growth, fabrication, and measurement of Hall-bar and Josephson junction devices in both material systems. We optimize surface quantum well heterostructure growth by molecular beam epitaxy (MBE) for single subband occupation and no parasitic parallel conduction. Electronic transport measurements in magnetic fields were carried out on the resulting heterostructures and analyzed. We highlight issues with the reproducibility of modulation-doped structures in InSb quantum wells and investigate the influence of doping density, buffer choice, growth parameters, and alloy composition on observed parallel conduction in the heterostructure. We show that nominally identical growths can differ by occupation of a parallel conduction channel. We also show that the window for modulation $\delta$ doping density between growths is smaller than the observed deviation in calibrated doping densities. We report on the growth, fabrication, and transport characteristics of high-quality, gate-tunable InSb two-dimensional electron gases (2DEGs) in surface quantum wells grown on (001) SI-GaAs substrates. We demonstrate the influence of modulation doping on gating characteristics, magnetotransport behavior, and spin-orbit interaction in two heterostructures, one with and one without a modulation-doped InAlSb layer. Magnetoresistance measurements confirm that intentional dopants in InSb are compatible with high-quality and reproducible transport characteristics, without parasitic parallel conduction or unstable carrier densities. This could be further tested in a 2DEG heterostructure with a short-period InSb/InAlSb superlattice doping scheme, where only the thin layer is doped. We present the first report of a surface quantum well in the lattice-matched InAs/AlGaSb material system on GaSb substrates. Deep quantum wells in this system have demonstrated record mobilities, by an order of magnitude, over the more commonly reported InAs/InGaAs system, making it a promising platform for topological quantum computing with Majorana zero modes. The surface of the quantum well is protected by lithography techniques designed to protect the surface from unnecessary chemical exposure during fabrication. Our results show that the carrier density is greatly enhanced in a surface quantum well compared to deeper structures and is highly influenced by the choice of gate dielectric in top-gated devices, often pushing the 2DEG into the second subband. However, the gating characteristics of the 2DEG show that the device can be tuned to a single-subband occupation. Josephson junctions with ex-situ sputtered contacts to these InAs surface quantum wells are fabricated using a surface passivation technique. Our lift-off process for ex-situ sputtered Nb/Ti contacts achieves smooth edges compatible with top-gated devices. We report the observation of induced superconductivity in undoped InAs surface quantum wells using this fabrication process. Two generations of SNS samples were fabricated with ebeam lithography and surface passivation techniques. The interface transparencies of the two generations of samples were determined. We observe a dependence of the critical current on junction length, corresponding to a sensitivity to elastic scattering in the semiconductor. The temperature dependence of the critical current in the junction with arbitrary transparency is modeled by the Kulik-Omelyanchuk relation. The measured excess current, resulting from Andreev reflection processes at the normal/superconducting (SN) interfaces, confirms the presence of phase-coherent behavior in our SNS devices. The process further achieves ex-situ high-transparency superconducting contacts in league with reports of epitaxial aluminum systems to InAs surface quantum wells.
Electron transport in semiconducting nanowires and quantum dots
(University of Waterloo, 2017-01-10) Holloway, Gregory; Baugh, Jonathan
Single electrons confined in electrostatic quantum dots are a promising platform for realizing spin based quantum information processing. In this scheme, the spin of each electron is encoded as a qubit, and can be manipulated and measured by modulating the gate voltages defining each dot. Since each qubit is realized in a single quantum dot, one could imagine scaling up this system by placing many quantum dots together in a tightly packed array. To be truly scalable each qubit must exhibit minimal variation, such that their behavior is consistent across the entire device. Transport through these quantum dots must therefore be explored in detail, to determine the source of these variations and design strategies to combat their effects. In this thesis a study of the transport properties of InAs nanowires and Si quantum dots is presented. In both systems the close proximity of the conduction electrons to defect-prone surfaces or interfaces causes them to be very sensitive to the physical properties of these regions. Through cryogenic transport measurements, and the development of relevant physical models, the effects of surface states, oxide charge traps, and interface defects are explored. In general these defects possess a finite charge, which modifies the electrostatic potential and alters electron transport. These additional changes to the electrostatic potential are detrimental for spin based quantum information processing, which requires precise control of this potential. In addition, the severity of each of these effects can be different in each device, leading to variation which limits scalability. By studying these effects we aim to better understand their properties and origins, such that they can be mitigated. Static defects, such as surface states, are found to be a dominant source of scattering that limits mobility. In InAs nanowires, we find that these effects can be removed through growth of an epitaxial shell that physically separates the nanowire surface from the conducting core. Dynamic defects on the other hand, lead to charge noise that shifts the potential causing instability. This noise originates from charge traps in close proximity to the conduction channel. For nanowires, the native oxide that forms at the surface is a likely location for these traps to occur. Through removal of this oxide and replacement with a defect free dielectric shell, greatly improved stability is observed. To test the viability of these fabrication techniques, nanowires treated with the most promising surface processes are used to fabricate top-gated nanowire field effect transistors. These devices are used to realize electrostatically defined double quantum dots, which show well controlled transport properties and minimal charge noise. In Si, electron transport is studied in a pair of capacitively coupled metal-oxide-semiconductor quantum dots. Here, the capacitive coupling is used implement charge sensing, such that the electrostatic potential of one dot can be measured down to the single electron regime. The pair of dots is also used to implement a novel memristive system which demonstrates current hysteresis. This shows the versatility of this system and its capability to control individual electrons, similar to the requirements needed to implement spin based quantum information processing.
Electronic Transport Properties in Single-layer CVD graphene
(University of Waterloo, 2023-01-23) Sakuragi, Mai; Baugh, Jonathan; Kim, Na Young
Graphene is a two-dimensional material of carbon atoms possessing a metallic nature and the low-energy quasiparticles behave as massless Dirac fermions. The unique electronic properties of graphene inspire many researches in fundamental physics, and its extraordinary mechanical strength and high thermal and electrical conductivity make graphene as potential material in the nano-electronic devices. The chemical vapor deposition (CVD) has enabled a large scale growth of graphene, and the applications such as magnetic field sensors and tunnelling transistors rely on the scalable fabrication techniques. However, charge carrier mobilities of CVD graphene reported so far are still relatively lower than exfoliated graphene due to the conventional wet-transfer method, and the state of the art technique to overcome this is the dry transfer or the encapsulation of graphene with hexagonal boron nitride (hBN). This thesis presents an experimental study of electronic transport properties in single-layer graphene. Hall bars are fabricated with 1cm$^2$-sized commercial CVD graphene using photolithography and \ce{O_2} plasma etching. The electric field effect and the Dirac point in graphene are characterized by applying an external gate voltage, and the magnetotransport in graphene is measured. The gate-voltage dependence on the weak-localization in the measured magnetoresistance is studied. Graphene samples are \textit{in-situ} annealed with high current density to remove the impurities on graphene surface and its effect on the electronic transport is studied. Lastly, the resistance in Ni/Au and Pd contacts is compared.
Heterostructure development and quantum control for semiconductor qubits
(University of Waterloo, 2022-01-04) Khromets, Bohdan; Baugh, Jonathan; Wasilewski, Zbigniew
States of confined electrons in semiconductors are promising candidates for quantum bits with high controllability, scalability, and coherence. Particularly, spin quantum dots offer direct integration with the modern MOS technology, whereas the exotic Majorana bound states are virtually immune to decoherence. In all cases, high-quality material system design is necessary for the fabrication of quantum devices, and the physical quantities that drive qubit operations require optimal pulse engineering for deterministic quantum control. The first goal of our study is to develop a consistent procedure of epitaxial InGaAs metallization with a flat Al layer and a pristine metal-semiconductor interface, necessary for the future observation of Majorana quasiparticles. The comprehensive analysis of the kinetics of Al on III-V heterostructures we carried out shows that the effects of deposition rate and methods of Al surface protection are understudied. With cross-sectional transmission electron microscopy, we demonstrate high heterostructure quality using As₄ as a capping layer and an order of magnitude larger Al deposition rate than previously reported. Based on the subsequent analysis for different Al growth rates and cappings, we conclude that faster rates are beneficial to minimize heat transfer to the wafer, protect the uncapped Al surface from rearrangement, and improve its morphology. Our second goal is to simulate the operation of a voltage- and ESR-controlled, quantum-dot-based spin quantum processor in silicon. To achieve this, we devise methods to extract the Hubbard model and spin interaction parameters from the electric potential landscape simulations of realistic device geometries. In addition, we present a novel, numerically efficient algorithm for voltage and ESR field pulse engineering that yields a theoretical 100% fidelity, preserves charge stability, and automatically incorporates all cross-couplings between quantum dots. The general optimal control formulation makes it possible to use the method in conjunction with gradient optimization routines. The algorithms are implemented as parts of a general-purpose, open-source Python package for semiconductor quantum dot simulations. We expect that the obtained results will further facilitate the development of semiconductor qubits, and become a stepping stone towards the realization of hybrid quantum dot-Majorana devices.
Quantum dot devices in silicon and dopant-free GaAs/AlGaAs heterostructures
(University of Waterloo, 2021-01-29) Buonacorsi, Brandon; Baugh, Jonathan; Laflamme, Raymond
Single spin quantum dot qubits in silicon are a promising candidate for a scalable quantum processor due to their long coherence times, compact size, and ease of integration into existing fabrication technologies. Realizing a large quantum processor composed of thousands or more logical qubits requires the integration of conventional transistor circuitry and wiring interconnects to control each individual dot in the processor. The high density of control wiring required for these processors presents many engineering challenges. In this thesis, we propose a surface code quantum processor for silicon quantum dot qubits based on a node/network architecture. Local nodes consisting of just seven quantum dots are spatially separated on the order of microns to facilitate space for the necessary high density wiring. Entanglement is distributed between individual nodes via shuttling of entangled electron pairs throughout the network. X or Z stabilizer operations, necessary for operating the surface code, are realized by distributing three electron spin singlet pairs across four local nodes followed by local gate operations and ancilla measurements. Simulations of electron shuttling indicate that adiabatic transport is possible on timescales that do not bottleneck the processor speed. Phase rotation of the shuttled spin, induced by the Stark shift, can lower the overall shuttling fi delity; however, the error can be mitigated by proper electrostatic tuning of the stationary electron's g-factor. Using realistic noise models, we estimate error thresholds with respect to single and two-qubit gate fidelities as well as singlet dephasing errors during shuttling. Electron shuttling is a key resource of the proposed network architecture. We continue the shuttling simulations by presenting an algorithm for finding constant-adiabatic shuttling control pulses, which enables a more rigorous study of how different conditions impact the shuttling speed and fidelity. These constant adiabatic pulses are used to optimize the physical device geometry to maximize charge shuttling speeds up to 300 nm/ns in the single-valley case. We then switch to an effective Hamiltonian representation where spin and valley degrees of freedom are accounted for during shuttling. Using realistic device and material parameters, shuttle speeds in the range 10-100 nm/ns with high spin entanglement fidelities are obtained when the tunneling energy exceeds the Zeeman energy. High fidelity shuttling also requires the inter-dot valley phase difference to be below a threshold determined by the ratio of tunneling and Zeeman energies, so that spin-valley-orbit mixing is weak. In this regime, we find that the primary source of infi delity is a coherent spin rotation that is correctable, in principle, using single spin rotations. Two-qubit gates in the network architecture are mediated by the exchange interaction, an interaction that stems from the Coulomb interaction but manifests as a rotation between the |0,1> and |1,0> two qubit states. Realizing fault tolerant two-qubit gates has proven difficult in silicon quantum dots due to charge noise which perturbs the electron orbitals states, causing decoherence. Quantitatively accurate modelling of exchange in general quantum dot networks is important towards realizing fault tolerant gates. Traditional modelling methods, such as a full con figuration interaction approach, are cumbersome due to significant computational overhead required when accounting for the electron-electron interactions in the calculation. We present a modi ed linear combination of harmonic orbitals con figuration interaction (LCHO-CI) approach which signifi cantly reduces the computational time for obtaining quantitatively accurate estimations of exchange. The method works by approximating the single electron orbitals of the quantum dot network using an orthogonal basis of harmonic orbitals. This choice of orthogonal basis allows a precalculated library of matrix elements to be used in evaluating the Coulomb interactions, which speeds up the LCHO-CI calculation. The modi ed LCHO-CI approach is then used to study how the physical device geometry impacts the charge noise sensitivity of a double quantum dot system. We fi nd that, in general, geometries which increase the dot charging energy and decrease the gate lever arms improve the system's sensitivity to charge noise. We conclude this thesis by pivoting away from theoretical studies of silicon quantum dots and towards experimental studies of electron transport in dopant-free GaAs heterostructures. In modulation doped GaAs heterostructures, a doping layer is used to induce a two-dimensional electron gas (2DEG) at the heterojunction. Dopant-free GaAs lack the doping layer which makes fabrication more difficult as local electron reservoirs must be used to bring carriers and induce a 2DEG. The lack of the doping layer offers several advantages over modulation doped heterostructures, such as gate-ability of the 2DEG and ability to make ambipolar devices (both n- and p-type ohmic contacts). Realizing n- and p-type ohmic contacts requires etching a recess pit and depositing the ohmic material at an angle in order to preventing screening of the top gate when inducing a 2DEG or two-dimensional hole gas (2DHG). Magnetotransport experiments are used to characterize an induced 2DEG and 2DHG in a Hall bar fabricated on a 310 nm deep single heterojunction. The carrier mobility and density can be tuned using the top gate, and we achieve peak mobility values of 4.5E6 cm2/Vs and 0.65E6 cm2/Vs for the 2DEG and 2DHG respectively. We then move to a one-dimensional system and study electron transport through a quantum point contact. Conductance quantization is observed, and subband spectroscopy measurements indicate a 1D subband spacing of 4.5 meV. Finally, we study dynamically driven electron transport in a zero-dimensional system using a tunable-barrier quantum dot acting as a single electron pump. Single electron pumping is observed up to T = 5 K, and fi ts to the electron cascade model suggests pumping errors of 1.87 ppm when operated at a driving frequency of f = 500 MHz.
Study of Surface Quantum Wells in InSb/AlInSb Heterostructures
(University of Waterloo, 2019-01-24) Bergeron, Emma; Baugh, Jonathan
The strong spin orbit coupling and large Lande g-factor of InSb compared to the other III-V semiconductors makes InSb an ideal choice for potential use in topological quantum computing with Majorana fermions. Furthermore, two dimensional electron gases (2DEGs) in III-V materials offer a more scalable platform for topological quantum computing over nanowire networks. Despite their ideal properties, 2DEGs in InSb have not been exploited for the purpose of studying Majorana fermions due to outstanding materials development challenges. This thesis presents an investigation of InSb/AlInSb heterostructures including surface quantum wells and standard high electron mobility transistor (HEMT) heterostructures. Development of fabrication methods and techniques is discussed for each system. Transport is characterized through mangetotransport measurements including quantum Hall effect and Shubnikov de-Haas oscillations. We extract carrier densities and mobilities for a series of wafers of varying doping densities. Gated structures allow further modulation of the carrier density and characterization of the effectiveness of gating is reported.
Superconducting Proximity Effect in Nanowire Josephson Junctions
(University of Waterloo, 2023-01-13) Gharavi, Kaveh; Baugh, Jonathan
Semiconducting nanowires contacted with superconductors are an interesting class of hybrid mesoscopic devices, in which charge transport is quantum mechanical due to the confinement potential of the nanowire, as well as the quantum mechanical nature of superconductivity. Especially interesting is the case where transport is phase coherent, resulting in the semiconductor inheriting certain properties of the superconductor (e.g. sustaining a dissipation-less current), a phenomenon called proximity superconductivity. Proximity effects allow for rich and interesting physics to occur at the intersection of superconductivity and mesoscopic transport, which are the subject of study in this thesis. Furthermore, proximitized nanowire devices with a strong spin-orbit coupling are promising candidates for the realization of Majorana bound states — quasiparticle states that are topological in nature and have enjoyed much recent attention due to their applications to topological quantum computing. As well as fundamental curiosity about proximity phenomena, it is imperative to fully understand them in order to utilize hybrid nanowire devices as the building blocks of a topological quantum computer. In this thesis we present experimental studies of three generations of Nb/InAs nanowire/Nb Josephson junctions in which proximity superconductivity is observed. Cryogenic transport measurements allow us to identify Andreev reflection as the mechanism behind the proximity effects — a mechanism wherein an electron incident on the superconductor/semiconductor interface is retro-reflected as a (conduction band) hole, carrying a charge equal to twice the electronic charge from the semiconductor into the superconductor, where it is carried as a Cooper pair. This mechanism is critically dependent on the transparency of the superconductor/semiconductor interface, whose qualities are successively improved over the three generations of devices. Further interesting and rich phenomena are also observed in the nanowire junctions, including Multiple Andreev reflections, Andreev bound states, and the likelihood of a novel form of Josephson interference called Orbital Josephson interference. We present theoretical and numerical studies that model these observed phenomena. Finally, we explore the relevance of this work to the topological quantum computing community by describing future challenges and experiments which can reveal the physics of Majorana bound states in similar systems. We give an in-depth proposal involving a proximitized nanowire and a quantum dot which can be used to verify the topological nature of the system, as well as read out the parity state of the Majorana bound states within the system.

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