Publication detail

Controlling surface charge and spin density oscillations by Dirac plasmon interaction in thin topological insulators

AMEEN POYLI, M. HRTOŇ, M. NECHAEV, I. NIKITIN, A. ECHENIQUE, P. SILKIN, V. AIZPURUA, J. ESTEBAN, R.

Original Title

Controlling surface charge and spin density oscillations by Dirac plasmon interaction in thin topological insulators

Type

journal article in Web of Science

Language

English

Original Abstract

Thin topological insulator (TI) films support optical and acoustic plasmonic modes characterized by effective net charge or net spin density, respectively.We combine many-body and electromagnetic calculations to study how these modes can be selectively excited at films and nanodisks at infrared and THz frequencies. We first discussthe excitation of propagating plasmons in a thin film by a point dipolar source. We emphasize how changing the distance between the dipolar source and the film allows us to control the relative strength of the acoustic and optical plasmons and thus to excite net-spin or net-charge waves on demand. The acoustic and optical modes in a nanodisk structure can be efficiently tuned by changing the size of the disk or by applying electrostatic gating. Furthermore, these modes can be confined to regions of dimensions much smaller than the wavelength. The control of the excitation of acoustic and optical modes indicates that thin topological insulators are a promising system to manipulate the spin and charge properties of the plasmonic response, with potential applications in fast, compact, and electrically-controlled spintronic devices.

Keywords

GRAPHENE PLASMONS; OPTICAL-PROPERTIES; BI2TE3; BI2SE3; NANOSTRUCTURES; RESONATORS; POLARITONS; FERMIONS; ANTENNAS; ARRAYS

Authors

AMEEN POYLI, M.; HRTOŇ, M.; NECHAEV, I.; NIKITIN, A.; ECHENIQUE, P.; SILKIN, V.; AIZPURUA, J.; ESTEBAN, R.

Released

15. 3. 2018

ISBN

2469-9950

Periodical

PHYSICAL REVIEW B

Year of study

97

Number

11

State

United States of America

Pages from

115420-1

Pages to

115420-14

Pages count

14