The University of Texas Rio Grande Valley

Department of Physics College of Sciences

Hamidreza Ramezani

Assistant Professor
Postdoc University of California Berkeley
Ph.D. Wesleyan University, 2013
M.S. University of Tehran, Iran, 2007
B.S. Shahed University, Iran, 2004
Office: Cavalry 207
Phone: 956-882-6648
Email: hamidreza.ramezani@utrgv.edu

Teaching

General Physics II

Research

The main theme of my research interested is in transport problems that are associated with waves including electronics, acoustics, optics and nanophotonics. This means that in my lab we cover a broad range of frequencies. My ultimate goal is to have a full control over waves. To this end, by means of synthetic metamaterials, we design complex potentials with unexpected responses, such as asymmetric transmission, unidirectional lasing, isolation, reconfigurable dynamics, ultra-sensitive responses, low threshold reactions, etc.

Optics and nano-Photonics: Synthetic manmade materials provides us with a great advantage to design artificial materials with enhanced functionalities. Examples of such materials are negative index materials, zero index materials and PT symmetric materials. PT symmetric materials are non-Hermitian structures that composed of active materials with balanced gain and loss. Depending on the degree of non-Hermiticity one can get spectrum which is completely real, partially real or completely imaginary. This provides us a powerful tool to engineer the band structure of the optical system and control the flow of light.

Acoustics: Intrinsic properties of materials in acoustic are the bulk modulus  and mass density . We showed that PT symmetric acoustics structures with complex intrinsic properties satisfying ,  have unique features. Generally, effective density (modulus) of acoustic material should have a negative (positive) part, indicating the material is lossy with inherent damping. Acoustic gain material has not yet been observed in nature, which however can be effectively realized by delicate feed-back systems using the active sound controlling apparatus. Similar to photonics we can observe peculiar dynamics in complex acoustics systems.

Electronics: Simple LRC circuits yet encompassing of all the novel features of PT symmetric systems can be used to demonstrate physics behind complex PT systems. Moreover, PT-LRC circuits will allow for efficient prediction of the behavior in more complicated applications such as active antenna arrays, electro-acoustic integration, or split-ring resonator metamaterial arrays, as they inevitably migrate into the realm of active elements inherent in PT systems.

Dr. Ramezani is currently seeking highly motivated graduate students to join his group at UTRGV. If you are a new student, interested in joining his group in Fall 2016 please apply to UTRGV Physics MS program. If you have any question, contact him via email.