What is the minimum fraction of the lasing molecules in a three-level laser that must be in the excited state in order for the laser to operate? Answer the same question for a four-level laser.

Q: Is it reasonable to expect superconductivity in a "glass," a material with almost no crystalline…

A: Introduction: This question discusses why a material with little or no crystal structure is…

Q: An abrupt silicon pn junction at zero bias has dopant concentrations of Nd = 5 X -3 -3 1017 cm-³ and…

A:

Q: Estimate kBT at room temperature, and convert this energy into electronvolts (eV). Using this…

A: The energy estimated in joules is, (Room temperature can be taken  as 300 K) E=kBTE=1.38×10-23…

Q: Consider an NMOS transistor fabricated in a 0.18-μm process with L = 0.18 μm and W = 2 μm. The…

A: Given: L=0.18μmW=2μmCox=8 fF/μm2μn=450cm2/V.sVtn=0.55VID=50μA

Q: In a phosphorus-doped silicon layer with impurity concentration of 1017/cm3, find the hole and…

A: Solution: Given that,                  Temperature, T = 300K We have to find out the electron and…

Q: Estimate kBT at room temperature, and convert this energy into electronvolts (eV). Using this…

A: The room temperature is about 300K. Determining the value of kBT, E=kBT=1.38×10-23 J/K300…

Q: Assume that at T-300 K, the electron mobility in a silicon sample is 1300 cm²/Vs If an electric…

A:

Q: Silicon is doped with 3×1018 arsenic atoms/cm3 and 8 × 1018 boron atoms/cm3. (a) Is this n- or…

A: Given , Silicon is doped with  2×1018 arsenic atoms/cm3 and 8×1018 boron atoms/cm3. Arsenic  is…

Q: Explain how a double heterostructure laser has both carrier confinement and optical confinement and…

A: In a homogeneous laser, the p-n junction acts as a means to achieve population inversion. The 'p'…

Q: b. The forbidden band is 0.7 eV in Ge and 1.1 eV in Si. How the conductivity of Ge does varies…

A: The problem is based on the concept of conductivity.  Conductivity is a measure of a material's…

Q: 1. a) Use the Fermi-Dirac distribution function with no approximations to determine the probability…

A: The Fermi-Dirac energy function gives the probability of an electron to posses energy according to…

Q: Calculate the total interfacial surface energy (in J) for 9 x 1018 spheres of copper, each with the…

A: As you know that total interfacial surface energy will be equal to:Esurface=4πr2 ×number of…

Q: An electron is moving in a piece of very lightly doped silicon under an applied field such that its…

A:

Q: I=1,(1-exp(-a x)

A: In the given equation  I=I01-exp-αxα=it is the absorption coefficient of the mediumI0=Initial…

Q: Conduct a literature search to find out what the lattice mismatch is between GaAs and AlAs at 300 K…

A: Solution given below:

Q: Calculate the planar density and planar packing fraction for the (010) and (020) planes in simple…

A:

Q: (a) what is he energy gap (in eV) between the valence and conduction bands for this photocell (b)…

A: wavelength of light = 1.11 micro meter this is the maximum wavelength at which electrons are able to…

Q: Estimate the energy difference (cm ) between the v 0, J= 0 level and the v = 1, J = 0 level. Based…

A: For pure vibrational energy levels, we can write, εv = (v + ½ ) ϖe – xe (v + ½ )2 ϖe - - - (1)…

Q: Derive an expression for the total number of states in semiconductor material (per unit volume)…

A: The total number of states per unit volume of semiconductor material between the energy Ec and Ec+kT…

Q: There is a one-dimensional lattice with lattice constant a as shown in Figure 1. An atom transits…

A: The average or mean displacement, x→=∑xi⇀pi After one step,(z seconds) xi→: +ai⏜           -ai⏜pi: p…

Q: You are depositing indium on a glass substrate. (a) Suppose that the surface energy of the substrate…

A:

Q: 1.7 A crystal has a basis of one atom per lattice point and a set of primitive translation vectors…

A: A crystal has a basis of one atom per lattice point and a set of primitive translation vectors (in…

Q: A 10 monolayers thick layer of Ag is deposited on Mo. The intensity of electrons emitted by the Ag…

A: Given:              10 monolayer of thick layer of Ag is deposited on Mo               Ratio of…

Q: Because of its semiconducting properties, CdSCdS is sometimes used in electronic devices. The band…

A: