Quantum edge effects biography
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Quantum Hall effect
Electromagnetic effect in physics
The quantum Hall effect (or integer quantum Hall effect) is a quantized version of the Hall effect which is observed in two-dimensional electron systems subjected to low temperatures and strong magnetic fields, in which the Hall resistanceRxy exhibits steps that take on the quantized values
where VHall is the Hall voltage, Ichannel is the channel current, e is the elementary charge and h is the Planck constant. The divisor ν can take on either integer (ν = 1, 2, 3,...) or fractional (ν = 1/3, 2/5, 3/7, 2/3, 3/5, 1/5, 2/9, 3/13, 5/2, 12/5,...) values. Here, ν is roughly but not exactly equal to the filling factor of Landau levels. The quantum Hall effect is referred to as the integer or fractional quantum Hall effect depending on whether ν is an integer or fraction, respectively.
The striking feature of the integer quantum Hall effect is the persistence of the quantization (i.e. the Hall plateau) as the electron density is varied. Since the electron density remains constant when the Fermi level is in a clean spectral gap, this situation correspon
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Recent advances in graphene quantum dot-based optical and electrochemical (bio)analytical sensors
* Corresponding authors
a Nanobiotechnology Laboratory, Department of Biosciences and Bioengineering, Indian Institute of Technology Roorkee, Roorkee 247667, Uttarakhand, India
E-mail:gopi@bt.iitr.ac.in, genegopi@gmail.com
Fax: +91-1332-273560
Tel: +91-1332-285650
b Department of Polymer and Process Engineering, Indian Institute of Technology Roorkee, Roorkee-247667, Uttarakhand, India
c Department of Electrical & Computer Engineering, University of Alberta, Edmonton, Canada
d Centre for Nanotechnology, Indian Institute of Technology Roorkee, Roorkee 247667, Uttarakhand, India
E-mail:rangadhar@gmail.com
Abstract
Since the day of their origin, the graphene quantum dots (GQDs) have been considered a predominant material for biosensing applications in view of their unique and exciting electronic, physicochemical and optical properties. By combining the quantum-confinement and edge effects of carbon dots with the graphene structure, GQDs have emerged as a wonder material. These photoluminescent QDs possess remarkable biocompatibility, high current density, fast electron mobility, high water solubility, good photochemica
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