Coherent electronic transfer in quantum dot systems using adiabatic passage

Abstract

We describe a scheme for using an all-electrical, rapid, adiabatic population transfer between two spatially separated dots in a triple-quantum dot system. The electron spends no time in the middle dot and does not change its energy during the transfer process. Although a coherent population transfer method, this scheme may well prove useful in incoherent electronic computation (for example quantum-dot cellular automata) where it may provide a coherent advantage to an otherwise incoherent device. It can also be thought of as a limiting case of type II quantum computing, where sufficient coherence exists for a single gate operation, but not for the preservation of superpositions after the operation. We extend our analysis to the case of many intervening dots and address the issue of transporting quantum information through a multi-dot system.

Strong coupling of a spin qubit to a superconducting stripline cavity

“…[5][6][7] The coupling of electron spins can be achieved via the exchange interaction, 8 which is short-ranged. Scaling up the spin-qubit architecture invariably requires on-chip quantum information transfer, whether via moving the electrons themselves [9][10][11] or via a "spin bus". 12 However, electron motion could lead to reduced spin coherence, 13 while the spin bus requires strong exchange couplings within a spin chain.…”

Coherent adiabatic transport of atoms in radio-frequency traps

“…Recently, it has been shown that similar techniques can, in principle, be used to control the quantized center-of-mass state of single particles [4][5][6]. This atom-optical analog has been dubbed coherent transport by adiabatic passage (CTAP) and while the possibility of observing this process has received significant attention [7,8], the conditions that have to be fulfilled for its observation are currently hard to achieve experimentally.…”

Information Free Quantum Bus for Generating Stabiliser States

“…The concept of flying qubits and quantum bus systems has received significant attention [15,16,17,18,19] as a means to combat the problem of long range transport in systems that do not exhibit them naturally. Bose introduced quantum state transfer via unmodulated spin chains [20], while teleportation hubs [21] have been proposed to combat long range transport in linear systems.…”