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Quantum mechanical estimation of cylindrical waveguide parameters with entropy computation

Authors:
L. Kumar at National Institute of Technology Delhi
L. Kumar
Vinay Shankar Pandey at National Institute of Technology Delhi
Vinay Shankar Pandey
Harish Parthasarathy at Netaji Subhas University of Technology, Dwarka
Harish Parthasarathy
  • Netaji Subhas University of Technology, Dwarka
Vibhakar Shrimali at GB Pant Govt. Engineering College Okhla Delhi
Vibhakar Shrimali
  • GB Pant Govt. Engineering College Okhla Delhi
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Abstract and Figures

This paper aims at first deriving the general forms of the electromagnetic vector and scalar potentials inside a cylindrical wave-guide by placing a 3D-charged quantum oscillator within the waveguide. The interaction Hamiltonian between the oscillator and the e-m field is derived. We then use this interaction Hamiltonian to calculate the transition probability of the oscillator from one stationary state to another. This calculation enables us to derive quantum mechanical algorithms for estimating the size of the waveguide. A problem that is useful in nano-level engineering is discussed. Finally an approximate expression for the amount of entropy pumped by e-m field into the atom is computed.
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Opt Quant Electron (2018) 50:201
https://doi.org/10.1007/s11082-018-1465-5
1 3
Quantum mechanical estimation ofcylindrical waveguide
parameters withentropy computation
L.Kumar1 · V.ShankarPandey2· H.Parthasarathy3· V.Shrimali4
Received: 4 March 2017 / Accepted: 12 April 2018 / Published online: 16 April 2018
© Springer Science+Business Media, LLC, part of Springer Nature 2018
Abstract This paper aims at first deriving the general forms of the electromagnetic vec-
tor and scalar potentials inside a cylindrical wave-guide by placing a 3D-charged quantum
oscillator within the waveguide. The interaction Hamiltonian between the oscillator and
the e-m field is derived. We then use this interaction Hamiltonian to calculate the transi-
tion probability of the oscillator from one stationary state to another. This calculation ena-
bles us to derive quantum mechanical algorithms for estimating the size of the waveguide.
A problem that is useful in nano-level engineering is discussed. Finally an approximate
expression for the amount of entropy pumped by e-m field into the atom is computed.
Keywords Schrödinger equation· 3D quantum harmonic oscillators· Waveguide·
Transition probability· Perturbation theory
1 Introduction
One of the outstanding problems in the discipline of nano-science and engineering is the
estimation of the waveguide parameters on nano-scale, which plays a vital role in the anal-
ysis of drugs in which a waveguide on the nano/quantum scale needs to be designed to
control the transitions in atoms and molecules. This enables us to alter their chemical prop-
erties which helps in the drug manufacture, such as an atom in which some of the electrons
* L. Kumar
lalitkumar_khanna@yahoo.com
1 Department ofElectronics andCommunication Engineering, National Institute ofTechnology,
Delhi, India
2 Department ofPhysics, National Institute ofTechnology, Delhi, India
3 Division ofElectronics andCommunication Engineering, Netaji Subhas Institute ofTechnology,
Delhi, India
4 Department ofElectronics andCommunication Engineering, G.B Pant Govt. Engineering College,
Delhi, India
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