Singlet-triplet filtering and entanglement in a quantum dot structure

TL;DR

This paper presents a method to generate and control spin entanglement in a quantum dot structure by exploiting singlet-triplet filtering through spin-dependent resonances, tunable via gate voltages.

Contribution

It introduces a novel singlet-triplet filtering mechanism in a complex quantum dot system, enabling tunable entanglement generation.

Findings

Filtering and entanglement can be controlled with gate voltages.

Exact time evolution shows effective singlet-triplet separation.

Spin-dependent resonances facilitate entanglement creation.

Abstract

We consider two interacting electrons in a semiconductor quantum dot structure which consists of a small dot within a larger dot, and demonstrate a singlet-triplet filtering mechanism which involves spin-dependent resonances and can generate entanglement. By studying the exact time evolution of singlet and triplet states we show how the degree of both filtering and spin entanglement can be tuned using a time-dependent gate voltage.