Quantum Control in Quantum Wells.

J. W. Clark, Dennis G. Lucarelli, Tzyh‐Jong Tarn

E. Räsänen, Thomas Blasi, Mario F. Borunda +1 more

We present theory and calculations for coherent high-fidelity quantum control of many-particle states in semiconductor quantum wells. We show that coupling a two-electron double quantum dot to a terahertz optical source enables targeted excitations that are one to two orders of magnitude faster and significantly more accurate than those obtained with electric gates. The optical fields subject to physical constraints are obtained through quantum optimal control theory that we apply in conjunction with the numerically exact solution of the time-dependent Schr\"odinger equation. Our ability to coherently control arbitrary two-electron states, and to maximize the entanglement, opens up further perspectives in solid-state quantum information.

Adriano A. Batista, David S. Citrin

We obtain pulse-driven population inversions in two-subband quantum wells (QW's) with a time-varying transition energy. We achieve this by using linearly chirped pulses with the center frequency given by a fit of the time-varying transition energy obtained from the effective nonlinear Bloch equations. The coherent population inversions (Rabi oscillations) are given for square QW's and for dc-biased square QW's. We further verify that the time-dependent polarization of the intersubband transitions can also be controlled.

G. Huang

Pavel Ginzburg, Meir Orenstein

We analyze slow light propagation in a coupled semiconductor quantum wells system exhibiting tunneling induced transparency. A group index as high as 85, for simple applicable GaAs/AlGaAs quantum wells structures, is predicted. Using DC voltage, the resonant tunneling rate can be altered and the related group index can be controlled over a broad range.

Shuang Cong