Coherent Light-Matter Interactions in Monolayer Transition-Metal Dichalcogenides

Edbert Jarvis Sie (Autor)

Buch | Hardcover

XVII, 129 Seiten

2017 | 1st ed. 2018
Springer International Publishing (Verlag)
978-3-319-69553-2 (ISBN)

Artikel merken

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 found in monolayer TMDs such as MoS2, WS2, and WSe2 are among the many novel properties exhibited by semiconductors when 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 experiments performed with a pump-probe technique using 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.

Edbert Jarvis Sie was awarded a PhD in physics by Massachusetts Institute of Technology in 2017. He is now a postdoctoral research fellow at Stanford University.

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.

Erscheinungsdatum	03.12.2017
Reihe/Serie	Springer Theses
Zusatzinfo	XVII, 129 p. 83 illus., 82 illus. in color.
Verlagsort	Cham
Sprache	englisch
Maße	155 x 235 mm
Gewicht	388 g
Themenwelt	Naturwissenschaften ► Physik / Astronomie ► Atom- / Kern- / Molekularphysik
	Naturwissenschaften ► Physik / Astronomie ► Festkörperphysik
	Naturwissenschaften ► Physik / Astronomie ► Theoretische Physik
Schlagworte	angle-resolved absorption spectroscopy • Bloch-Siegert effect • coherent light-matter interactions • electronic valleys • optical Stark effect • time-resolved absorption spectroscopy • valleytronics • XUV spectroscopy
ISBN-10	3-319-69553-3 / 3319695533
ISBN-13	978-3-319-69553-2 / 9783319695532
Zustand	Neuware