Quantum interference capacitor based on double-passage Landau-Zener-Stückelberg-Majorana interferometry

Abstract

The implementation of quantum technologies in electronics leads naturally to the concept of coherent singleelectron circuits, in which a single charge is used coherently to provide enhanced performance. In this work, we propose a coherent single-electron device that operates as an electrically-tunable capacitor. This system exhibits a sinusoidal dependence of the capacitance with voltage, in which the amplitude of the capacitance changes and the voltage period can be tuned by electric means. The device concept is based on double-passage Landau-Zener-Stückelberg-Majorana interferometry of a coupled two-level system that is further tunnel-coupled to an electron reservoir. We test this model experimentally by performing Landau-Zener-Stückelberg-Majorana interferometry in a single-electron double quantum dot coupled to an electron reservoir and show that the voltage period of the capacitance oscillations is directly proportional to the excitation frequency and that the amplitude of the oscillations depends on the dynamical parameters of the system: intrinsic relaxation and coherence time, as well as the tunneling rate to the reservoir. Our work opens up an opportunity to use the non-linear capacitance of double quantum dots to obtain enhanced device functionalities.

Quantum Control via Landau-Zener-Stückelberg-Majorana Transitions

“…Consider a transition rate in a driven TLS, following (Berns et al, 2006) [see also (Otxoa et al, 2019)]. This is described by the Hamiltonian…”

Analog of a quantum heat engine using a single-spin qubit

“…The pulse length is expected to be about 0.1-1 µs from the previous Rabi oscillation experiment (Ref. [28]). However, such experiments have not been possible because the current experimental setup does not have enough equipment to perform this pulsing.…”

“…When decreasing the ratio of the driving period, 2π/Ω, to the decoherence time T 2 , we expect that the coherence will result in interference between the wave-function components [25][26][27][28]. This regime, when T 2 2π/Ω, can be denoted as a coherent regime.…”

Measurement of tunnel coupling in a Si double quantum dot based on charge sensing

“…Tunnel coupling is an essential element in coherent manipulation of electron qubits in semiconductor quantum dots (QDs) [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18]. It allows single-qubit operations on a charge qubit, and exchange gates for spin qubits [19][20][21][22][23][24][25].…”