UNT UNT NanotechNanotech

Ultrafast and Nanoscale Photonics Group Arup Neogi, Department of Physics

Research AreasResearch Areas

1. Nanostructured Optoelectronic materials for efficient light emission2. Biophotonic materials; for hybrid molecular electronics and photonics

http://www.phys.unt.edu/research/photonic/website/

Sponsors:• National Science Foundation• US Department of Energy• Japan Soc. for Promotion of Sciences

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* MRS Best paper award 2005

GaN

Photocurrent measurement shows a semiconductor like behavior with a cut-off wavelength at 327 nm (3.79 eV), larger than silicon devices, at lower bias. The bandgap also changes with bias.

Oligonucleotide based Single Molecule

Nanoscale UV Photodetector (A. Neogi et al)

Self-assembled guaninosine molecule with strong intrinsic dipole moment I-V characteristics of GaN based single

molecule guaninosine photodetector showing rectification at 100 nm length of self-assembled organic crystal.

Objectives:

To develop GaN based novel hybrid molecular semiconductors for UV-visible photodetectors

280 300 320 340 360 380 400 420 440 4606.96

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Wavelength (nm)

54 Device

UNT UNT NanotechNanotech

GaN Semiconductor Quantum dots based light emitters (A. Neogi)

Near-field emission from a single cluster of GaN/AlN quantum dot for UV light emission

344 nm –347 nm