1.

Record Nr.

UNINA9910300551003321

Autore

Sie Edbert Jarvis

Titolo

Coherent Light-Matter Interactions in Monolayer Transition-Metal Dichalcogenides [[electronic resource] /] / by Edbert Jarvis Sie

Pubbl/distr/stampa

Cham : , : Springer International Publishing : , : Imprint : Springer, , 2018

ISBN

3-319-69554-1

Edizione

[1st ed. 2018.]

Descrizione fisica

1 online resource (XVII, 129 p. 83 illus., 82 illus. in color.)

Collana

Springer Theses, Recognizing Outstanding Ph.D. Research, , 2190-5053

Disciplina

541.33

Soggetti

Surfaces (Physics)

Interfaces (Physical sciences)

Thin films

Optical materials

Electronic materials

Spectroscopy

Microscopy

Lasers

Photonics

Semiconductors

Atoms

Physics

Surface and Interface Science, Thin Films

Optical and Electronic Materials

Spectroscopy and Microscopy

Optics, Lasers, Photonics, Optical Devices

Atoms and Molecules in Strong Fields, Laser Matter Interaction

Lingua di pubblicazione

Inglese

Formato

Materiale a stampa

Livello bibliografico

Monografia

Nota di bibliografia

Includes bibliographical references.

Nota di contenuto

Chapter1. Introduction -- Chapter2. Time-resolved absorption spectroscopy -- Chapter3. Intervalley biexcitons in monolayer MoS2 -- Chapter4. Valley-selective optical Stark effect in monolayer WS2 -- Chapter5. Intervalley biexcitonic optical Stark effect in monolayer WS2



-- Chapter6. Large, valley-exclusive Bloch--Siegert shift in monolayer WS2 -- Chapter7. Lennard--Jones-like potential of 2D excitons in monolayer WS2 -- Chapter8. WUV based Time-resolved ARPES.

Sommario/riassunto

This thesis presents optical methods to split the energy levels of electronic valleys in transition-metal dichalcogenides (TMDs) by means of coherent light-matter interactions. The electronic valleys present in monolayer TMDs such as MoS2, WS2, and WSe2 are among the many novel properties exhibited by semiconductors thinned down to a few atomic layers, and have have been proposed as a new way to carry information in next generation devices (so-called valleytronics). These valleys are, however, normally locked in the same energy level, which limits their potential use for applications. The author describes experiment performed with a pump-probe technique using a transient absorption spectroscopy on MoS2 and WS2. It is demonstrated that hybridizing the electronic valleys with light allows one to optically tune their energy levels in a controllable valley-selective manner. In particular, by using off-resonance circularly polarized light at small detuning, one can tune the energy level of one valley through the optical Stark effect. Also presented within are observations, at larger detuning, of a separate contribution from the so-called Bloch--Siegert effect, a delicate phenomenon that has eluded direct observation in solids. The two effects obey opposite selection rules, enabling one to separate the two effects at two different valleys.