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Related papers: Highly tuneable hole quantum dots in Ge-Si core-sh…

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Hole spin qubits in planar Ge heterostructures are one of the frontrunner platforms for scalable quantum computers. In these systems, the spin-orbit interactions permit efficient all-electric qubit control. We propose a minimal design…

Mesoscale and Nanoscale Physics · Physics 2021-09-29 Stefano Bosco , Mónica Benito , Christoph Adelsberger , Daniel Loss

We investigate hole spin relaxation in the single- and multi-hole regime in a 2x2 germanium quantum dot array. We use radiofrequency (rf) charge sensing and observe Pauli Spin-Blockade (PSB) for every second interdot transition up to the…

Mesoscale and Nanoscale Physics · Physics 2021-01-26 W. I. L. Lawrie , N. W. Hendrickx , F. van Riggelen , M. Russ , L. Petit , A. Sammak , G. Scappucci , M. Veldhorst

Motivated by the recently demonstrated ability to attach quantum dots to polymers at well defined locations, we propose a condensed phase analog of the ion trap quantum computer: a scheme for quantum computation using chemically assembled…

Quantum Physics · Physics 2009-11-07 K. R. Brown , D. A. Lidar , K. B. Whaley

Quantum networks based on InGaAs quantum dots embedded in photonic crystal devices rely on QDs being in resonance with each other and with the cavities they are embedded in. We developed a new technique based on temperature tuning to…

Quantum Physics · Physics 2009-11-13 Andrei Faraon , Dirk Englund , Ilya Fushman , Nick Stoltz , Pierre Petroff , Jelena Vuckovic

Tuning a material to the cusp between two distinct ground states can produce exotic physical properties, unlike those in either of the neighboring phases. The prospect of designing a model experimental system to capture such behavior is…

We show that fully self-assembled optically-active quantum dots (QDs) embedded in MBE-grown GaAs/AlGaAs core-shell nanowires (NWs) are coupled to the NW mechanical motion. Oscillations of the NW modulate the QD emission energy in a broad…

Mesoscale and Nanoscale Physics · Physics 2014-08-22 M. Montinaro , G. Wüst , M. Munsch , Y. Fontana , E. Russo-Averchi , M. Heiss , A. Fontcuberta i Morral , R. J. Warburton , M. Poggio

Spin-based semiconductor qubits hold promise for scalable quantum computing, yet they require reliable autonomous calibration procedures. This study presents an experimental demonstration of online single-dot charge autotuning using a…

Thin (6-7 quintuple layer) topological insulator Bi2Se3 quantum dot devices are demonstrated using ultrathin (2~4 quintuple layer) Bi2Se3 regions to realize semiconducting barriers which may be tuned from Ohmic to tunneling conduction via…

Mesoscale and Nanoscale Physics · Physics 2012-01-19 Sungjae Cho , Dohun Kim , Paul Syers , Nicholas P. Butch , Johnpierre Paglione , Michael S. Fuhrer

Universal quantum computation requires high fidelity single qubit rotations and controlled two qubit gates. Along with high fidelity single qubit gates, strong efforts have been made in developing robust two qubit logic gates in…

Mesoscale and Nanoscale Physics · Physics 2016-10-20 D. R. Ward , Dohun Kim , D. E. Savage , M. G. Lagally , R. H. Foote , Mark Friesen , S. N. Coppersmith , Mark A. Eriksson

We present transport measurements through an electrostatically defined bilayer graphene double quantum dot in the single electron regime. With the help of a back gate, two split gates and two finger gates we are able to control the number…

Mesoscale and Nanoscale Physics · Physics 2020-04-22 Luca Banszerus , Samuel Möller , Eike Icking , Kenji Watanabe , Takashi Taniguchi , Christian Volk , Christoph Stampfer

We report on developing split-gate quantum point contacts (QPCs) that have a tunable length for the transport channel. The QPCs were realized in a GaAs/AlGaAs heterostructure with a two- dimensional electron gas (2DEG) below its surface.…

Mesoscale and Nanoscale Physics · Physics 2013-01-15 M. J. Iqbal , J. P. de. Jong , D. Reuter , A. D. Wieck , C. H. van der Wal

Most proof-of-principle experiments for spin qubits have been performed using GaAs-based quantum dots because of the excellent control they offer over tunneling barriers and the orbital and spin degrees of freedom. Here, we present the…

Large-scale arrays of quantum-dot spin qubits in Si/SiGe quantum wells require large or tunable energy splittings of the valley states associated with degenerate conduction band minima. Existing proposals to deterministically enhance the…

The spin states of single electrons in gate-defined quantum dots satisfy crucial requirements for a practical quantum computer. These include extremely long coherence times, high-fidelity quantum operation, and the ability to shuttle…

The long term scaling prospects for solid-state quantum computing architectures relies heavily on the ability to simply and reliably measure and control the coherent electron interaction strength, known as the tunnel coupling, $t_c$. Here,…

We perform an excited state spectroscopy analysis of a silicon corner dot in a nanowire field-effect transistor to assess the electric field tunability of the valley splitting. First, we demonstrate a back-gate-controlled transition between…

Atomically flat semiconductor nanostructures have sharp photoluminescence emission, short radiative lifetimes and a well-defined planar structure. However, these nanostructures lack the optical and electronic fine-tuning that justify…

Materials Science · Physics 2015-09-29 Sébastien Lamarre , Étienne Rochette , Samuel Tremblay , Claudine Nì. Allen

Self-organized semiconductor quantum dots represent almost ideal two-level systems, which have strong potential to applications in photonic quantum technologies. For instance, they can act as emitters in close-to-ideal quantum light…

We report the realization of nanotube-based quantum dot structures that use local electrostatic gating to produce individually controllable dots in series along a nanotube. Electrostatic top-gates produce depletion regions in the underlying…

Mesoscale and Nanoscale Physics · Physics 2015-06-25 M. J. Biercuk , S. Garaj , N. Mason , J. M. Chow , C. M. Marcus

Measurement of charge configurations in few-electron quantum dots is a vital technique for spin-based quantum information processing. While fast and high-fidelity measurement is possible by using proximal quantum dot charge sensors, their…

Mesoscale and Nanoscale Physics · Physics 2021-03-30 Takashi Nakajima , Yohei Kojima , Yoshihiro Uehara , Akito Noiri , Kenta Takeda , Takashi Kobayashi , Seigo Tarucha