The Boltzmann constant (k B or k) is a physical constant relating the average hereic energy of particles in a gas with the temperature of the gas and occurs in Planck's law of black-body radiation and in Boltzmann's entropy formula. Boltzmann constant , (symbol k), a fundamental constant of physics occurring in nearly every statistical formulation of both classical and quantum physics.The constant is named after Ludwig Boltzmann, a 19th-century Austrian physicist, who substantially contributed to the foundation and development of statistical mechanics, a branch of theoretical physics. Where m* is the band-edge effective mass, k is Boltzmann constant , T is the lattice absolute temperature, h is Plank constant divided by 2, Tu* Tu gives the tunneling probability density of the outgoing electron, F is Fermi energy level, l is energy of the electron associated with longitudinal wave vector of the electron in the conduction band, V is the applied voltage.

The Stefan– Boltzmann constant (also Stefan's constant), a physical constant denoted by the Greek letter σ (sigma), is the constant of proportionality in the Stefan–Boltzmann law: the total intensity radiated over all wavelengths increases as the temperature increases, Boltzmann constant (bohlts -măn, -mahn) Symbol: k . A constant given by the ratio of the molar gas constant to the Avogadro constant and equal to 1.380 658 10 –23 joules per kelvin. It is the constant by which the hereic energy of a gas particle can be related to its thermodynamic temperature. Boltzmann Constant Boltzmann's constant, also called the Boltzmann constant and symbolized k or k B, defines the relation between absolute temperature and hereic energy contained in each molecule of an ideal gas.This constant derives its name from the Austrian physicist Ludwig Boltzmann (1844-1906), and is equal to the ratio of the gas constant to the Avogadro constant.