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Related papers: Optimal control of universal quantum gates in a do…

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In this paper, we demonstrate that optimal control algorithms can be used to speed up the implementation of modules of quantum algorithms or quantum simulations in networks of coupled qubits. The gain is most prominent in realistic cases,…

Quantum Physics · Physics 2008-12-20 T. Schulte-Herbrueggen , A. K. Spoerl , N. Khaneja , S. J. Glaser

We present a theory of electronic properties and the spin blockade phenomena in a gated linear triple quantum dot. Quadruple points where four different charge configurations are on resonance, particularly involving (1,1,1) configuration,…

Mesoscale and Nanoscale Physics · Physics 2015-05-30 Chang-Yu Hsieh , Yun-Pil Shim , Pawel Hawrylak

Implementing fast and high-fidelity quantum operations using open-loop quantum optimal control relies on having an accurate model of the quantum dynamics. Any deviations between this model and the complete dynamics of the device, such as…

Quantum Physics · Physics 2024-10-31 Elie Genois , Noah J. Stevenson , Noah Goss , Irfan Siddiqi , Alexandre Blais

A quantum information processing scheme is proposed with semiconductor quantum dots located in a high-Q single mode QED cavity. The spin degrees of freedom of one excess conduction electron of the quantum dots are employed as qubits.…

Quantum Physics · Physics 2009-11-07 Mang Feng , Irene D'Amico , Paolo Zanardi , Fausto Rossi

Influence of resonant oscillating electromagnetic field on a single electron in coupled lateral quantum dots in the presence of phonon-induced relaxation and decoherence is investigated. Using symmetry arguments it is shown that spin and…

Mesoscale and Nanoscale Physics · Physics 2013-05-29 Peter Stano , Jaroslav Fabian

It is shown that anisotropic spin chains with gapped bulk excitations and magnetically ordered ground states offer a promising platform for quantum computation, which bridges the conventional single-spin-based qubit concept with recently…

Mesoscale and Nanoscale Physics · Physics 2011-10-14 Yaroslav Tserkovnyak , Daniel Loss

Quantum computation with electron spin qubits requires coherent and efficient manipulation of these spins, typically accomplished through the application of alternating magnetic or electric fields for electron spin resonance (ESR). In…

A spin qubit in semiconductor quantum dots holds promise for quantum information processing for scalability and long coherence time. An important semiconductor qubit system is a double quantum dot trapping two electrons or holes, whose spin…

Mesoscale and Nanoscale Physics · Physics 2021-09-07 Peihao Huang

We present a theory of quantum circuits based on logical qubits encoded in chirality of electron spin complexes in lateral gated semiconductor triple quantum dot molecules with one electron spin in each dot. Using microscopic Hamiltonian we…

Strongly Correlated Electrons · Physics 2015-05-18 Chang-Yu Hsieh , Pawel Hawrylak

Advances in quantum technologies are often limited by slow device characterization, complex tuning requirements, and scalability challenges. Spin qubits in electrostatically defined quantum dots provide a promising platform but are not…

A doped semiconductor double-quantum-dot molecule is proposed as a qubit realization. The quantum information is encoded in the electron spin, thus benefiting from the long relevant decoherence times; the enhanced flexibility of the…

Mesoscale and Nanoscale Physics · Physics 2009-11-10 F. Troiani , U. Hohenester , E. Molinari

We theoretically study single and two-qubit dynamics in the circuit QED architecture. We focus on the current experimental design [Wallraff et al., Nature 431, 162 (2004); Schuster et al., Nature 445, 515 (2007)] in which superconducting…

Mesoscale and Nanoscale Physics · Physics 2009-11-11 Alexandre Blais , Jay Gambetta , A. Wallraff , D. I. Schuster , S. M. Girvin , M. H. Devoret , R. J. Schoelkopf

Quantum spin Hall insulators, recently realized in HgTe/(Hg,Cd)Te quantum wells, support topologically protected, linearly dispersing edge states with spin-momentum locking. A local magnetic exchange field can open a gap for the edge…

Mesoscale and Nanoscale Physics · Physics 2013-05-30 Carsten Timm

A double-quantum-dot coupled to electrodes with spin-dependent splitting of chemical potentials (spin bias) is investigated theoretically by means of the Green's functions formalism. By applying a large spin bias, the quantum spin in a…

Mesoscale and Nanoscale Physics · Physics 2008-06-16 Hai-Zhou Lu , Shun-Qing Shen

We propose a method to electrically control electron spins in donor-based qubits in silicon. By taking advantage of the hyperfine coupling difference between a single-donor and a two-donor quantum dot, spin rotation can be driven by…

Mesoscale and Nanoscale Physics · Physics 2017-03-17 Yu Wang , Chin-Yi Chen , Gerhard Klimeck , Michelle Y. Simmons , Rajib Rahman

We present some compact quantum circuits for a deterministic quantum computing on electron-spin qubits assisted by quantum dots inside single-side optical microcavities, including the CNOT, Toffoli, and Fredkin gates. They are constructed…

Quantum Physics · Physics 2015-03-03 Hai-Rui Wei , Fu-Guo Deng

Taking the excess electron spin in a unit cell of semiconductor multiple quantum-dot structure as a qubit, we can implement scalable quantum computation without resorting to spin-spin interactions. The technique of single electron…

Quantum Physics · Physics 2007-05-23 Wei-Min Zhang , Yin-Zhong Wu , Chopin Soo

We demonstrate how gradient ascent pulse engineering optimal control methods can be implemented on donor electron spin qubits in Si semiconductors with an architecture complementary to the original Kane's proposal. We focus on the…

Mesoscale and Nanoscale Physics · Physics 2015-05-13 Dong-Bang Tsai , Po-Wen Chen , Hsi-Sheng Goan

The dynamics of a quantum system driven by an external field is well described by a unitary transformation generated by a time dependent Hamiltonian. The inverse problem of finding the field that generates a specific unitary transformation…

Quantum Physics · Physics 2009-11-10 Jose P. Palao , R. Kosloff

Optical techniques have been employed to coherently control the quantum transport through nanojunctions. Conventional works on optical control of quantum transport usually applied a tailored electrical pulses to perform specific tasks. In…

Mesoscale and Nanoscale Physics · Physics 2015-10-13 Yu Zhang