Efficient Biexciton State Preparation in a Semiconductor Quantum Dot‐Metallic Nanoparticle Hybrid Structure Using Transitionless Quantum Driving

Abstract

How to efficiently prepare the biexciton state in a semiconductor quantum dot placed in the vicinity of a metal nanoparticle is investigated, with control pulses calculated using shortcuts to adiabaticity and specificaly transitionless quantum driving. The quantum dot is considered to be initialized in its ground state. It is numerically demonstrated that the proposed scheme can generate biexciton population values close to unity, for a broad span of interparticle distances and small to moderate values of the biexciton binding energy, when using short laser pulses. It is also shown that these results are robust for small errors in the nanoparticle placement. When the interparticle distance is decreased or the duration of the applied pulses is increased, the population transfer to the biexciton state is reduced. The reason is that for shorter distances the nonlinear terms in the density matrix equation, arising due to exciton-plasmon interaction, become stronger, while for longer pulses the influence of these unwanted terms is prolonged. Similarly, the fidelity is also reduced for larger values of the biexciton binding energy and longer pulses. This work may be exploited in research fields like quantum information processing and high speed nanoswitches, where a key procedure is the efficient biexciton state preparation in quantum dots.

Flexible preparation of the W state via the GRAPE algorithm in a nanoring-quantum-dot system

“…The expression for the coupling strength Ω j (t) is given by Ω j (t) = −µE zj (t), where µ denotes the dipole moment of the QD, and E zj (t) is the strength of the electric field in the direction perpendicular to the metal nanoring interface [53,54]. The form of E zj (t) reads [55]…”

Susceptibility in a Coupled Double Quantum Dot-Metal Nanoparticle System under Standing Wave Field

“…The distance between particles was represented by and appeared to be longer than the MNP's radius ( ) [14,17] where relates to any one of the two QDs' radius. A gold (Au) sphere is the MNP that was frequently utilized in the references [1, [3][4][5][6][7][8]17]. DQD is made up of two QDs, an InAs with a height of and a radius of on a disk shape.…”

“…Thus, it modifies the electromagnetic field experienced by quantum systems. Additionally, the optical properties of Nano systems like QDs with plasmonic nanoparticles, metallic nanorods and spherical nanoparticles, have recently attracted a lot of attention [1][2][3][4].…”