High temperature Graphene-based Quantum Hall Effect Infrared photodetector*

We demonstrate successful operation of quantum Hall effect (QHE) graphene-based detectors at 70K, a temperature achievable using simple pumped liquid Nitrogen cryostats, and in magnetic field of 7.35T. Because of graphene's unique band structure, the first few Landau levels are well-separated energetically, thus allowing observation and manipulation of QHE at unprecedentedly high temperatures [1]. Our results overcome the obstacle of low operating temperature of traditional semiconductor systems-based QHE photodetectors [2], and open the door for wide arrays of applications. \\[4pt] [1] K.S. Novoselov \textit{et al}. \textit{Science} \textbf{315}, 1379 (2007).\\[0pt] [2] N. G. Kalugin \textit{et.al.} \textit{Phys.Rev.B} 66, 085308 (2002).