Seminar: "Emission and Detection of THz Radiation Using Graphene and III‐V Semiconductor Heterostructures" by Prof. Stephane Albon Boubanga Tombet

Dear All,

Femtosecond Spectroscopy Unit (Dani Unit) would like to invite you to a seminar by Prof. Stephane Boubanga Tombet as follows.

Date: October 30th Fri, 2015

Time: 11:00- 12:00

Venue: Seminar Room B503 (Center)

Speaker: Prof. Stephane Boubanga Tombet, RIEC, Tohoku University, Sendai Japan

Title:   Emission and Detection of THz Radiation Using Graphene and III‐V Semiconductor Heterostructures

Abstract:

         Recent advances in emission and detection of terahertz (THz) radiation using graphene and III‐V semiconductors are presented. First topic focuses on graphene, a monolayer carbon‐atomic honeycomb lattice crystal, exhibiting peculiar carrier transport and optoelectronic/plasmonic properties owing to massless and gapless energy spectrum. Theoretical and experimental studies toward the creation of graphene terahertz injection lasers are described [1-4].

         Second the two dimensional plasmons in III‐V semiconductor heterostructures  re discussed for emission and detection of THz radiation. The device structure is based on a high‐electron mobility transistor and incorporates the author’s original asymmetrically interdigitated dual‐grating gates [5,6].

Biography:

             Stephane Albon Boubanga Tombet received his MS and PhD degrees in condensed matter physics from Montpellier 2 University   in France in 2005 and 2008, respectively. From 2008 to 2009, he worked for Montpellier 2 University as a teacher and research assistant. From 2009 to 2011, he joined the Research Institute of Electrical Communication, Tohoku University, in Sendai, as a postdoctoral researcher granted by the Japanese Society for the Promotion of Science (JSPS). After that he Los Alamos National Labs in New Mexico as a postdoctoral researcher until Jun 2013. He is currently working as an Associate Professor at the Research Institute of Electrical Communication, Tohoku University. His current research interests include III-V based plasmonics based emitters and receivers in the millimeter-wave and terahertz regions, graphene based materials/devices, gaphene active plasmonics and their terahertz applications.

REFERENCES

[1] V. Ryzhii et al., J. Appl. Phys. 101, 083114 (2007). 

[2] T. Otsuji et al., IEEE J. Select. Topics in Quantum Electron. 19, 8400209 (2013).

 [3] S. Boubanga Tombet et al., Phys. Rev. B 85, 035443  (2012)

[4] ] T. Watanabe et al., New J. Phys. 15, 075003 (2013).

 [5] ] S. Boubanga Tombet et al., Appl. Phys. Lett., Vol. 104, pp. 262104-1-4, 2014

 [6] Y. Kurita et al. Appl. Phys. Lett., Vol. 104, pp. 251114-1-4, 2014

We look forward to seeing many of you at the seminar.

Sincerely yours,

Yumi Ito

Dani Unit