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1. Department of Physics, Govt. Zirtiri Residential Science College, Aizawl 796 001, India
2. Nuclear Physics Division, Bhabha Atomic Research Center, Tombay, Mumbai, India
3. Department of Physics, Mizoram University, Aizawl 796 009, India
Received: November 29, 2010 / Accepted: February 24, 2011 / Published: February 25, 2012.
Abstract: This paper presented a simple model calculation of photofield emission current (PFEC) from tungsten. For evaluation of the matrix element, Kronig-Penney potential model for the crystal is used for deducing the required wavefunctions. Interpolation method is used in the dielectric model for calculations of vector potential of interest.
Photofield emission (PFE) is a technique in which a metal is irradiated by an incident laser radiation of photon energy (??). Photon energy is usually less than the work function (?) of the metal. The incident radiation photoexcites the electrons to states which lies between the Fermi level and the vacuum level, hence these electrons are confined within the metal surface. A strong static electric field (~ 109 V/m) when applied to the surface of the metal causes the photoexcited electrons to tunnel through the surface potential barrier into the surrounding vacuum. These electrons which are now emitted into the vacuum region constitute the measurable current called photofield emission current(PFEC). For the evaluation of PFEC, the initial state wavefunction as deduced Thapa and Kar [1] by using the Kronig-Penney potential model will be used. Dielectric model proposed by Bagchi and Kar [2] is used for obtaining the vector potential of interest. Calculated PFEC is compared with the result of Gao
2. Nuclear Physics Division, Bhabha Atomic Research Center, Tombay, Mumbai, India
3. Department of Physics, Mizoram University, Aizawl 796 009, India
Received: November 29, 2010 / Accepted: February 24, 2011 / Published: February 25, 2012.
Abstract: This paper presented a simple model calculation of photofield emission current (PFEC) from tungsten. For evaluation of the matrix element, Kronig-Penney potential model for the crystal is used for deducing the required wavefunctions. Interpolation method is used in the dielectric model for calculations of vector potential of interest.
Photofield emission (PFE) is a technique in which a metal is irradiated by an incident laser radiation of photon energy (??). Photon energy is usually less than the work function (?) of the metal. The incident radiation photoexcites the electrons to states which lies between the Fermi level and the vacuum level, hence these electrons are confined within the metal surface. A strong static electric field (~ 109 V/m) when applied to the surface of the metal causes the photoexcited electrons to tunnel through the surface potential barrier into the surrounding vacuum. These electrons which are now emitted into the vacuum region constitute the measurable current called photofield emission current(PFEC). For the evaluation of PFEC, the initial state wavefunction as deduced Thapa and Kar [1] by using the Kronig-Penney potential model will be used. Dielectric model proposed by Bagchi and Kar [2] is used for obtaining the vector potential of interest. Calculated PFEC is compared with the result of Gao