State Preparation Schemes for Solid-State Quantum Emitters

Prof. Doris Reiter from TU Dortmund (formerly of WWU Münster) will give a talk on "State Preparation Schemes for Solid-State Quantum Emitters". This talk will take place at 3pm in DB113 and will be streamed/recorded via Teams.

A prerequisite for photonic quantum technologies is the generation of specific photon states. Single photons can be created by a two-level quantum emitter, which has been prepared in its excited state, while the generation of entangled photon states requires multi-level quantum systems.

In this talk, I will give an overview over different state preparation schemes for solid-state quantum emitters [1]. As a working horse I will focus on semiconductor quantum dots. A major difference between atomic and solid-state emitters is the interaction with the lattice vibration, i.e., the phonons. In most applications, the phonons are detrimental to the ideal photon generation, such that parameter regimes are identified where their influence is minimal. A special regime is the reappearance regime at strong excitation strength, where the phonons decouple from the electronic degrees of freedom. On the other hand, phonon-assisted preparation schemes make active use of phonons. In a radically new preparation scheme, the so-called SUPER scheme, an excitation below the transition energy with two pulses results in the preparation of the excited state [2,3], though a single pulse would not change the final state occupation at all.

In search for the perfect quantum light emitting device, understanding and implementing the best protocol is an important step towards the realization of quantum devices.

References
[1] S. Lüker and D. E. Reiter, Semicond. Sci. Technol. 34, 063002 (2019)
[2] T. K. Bracht et al., PRX Quantum 2, 040354 (2022)
[3] Y. Karli et al., arXiv preprint arXiv:2203.00712 (2022)