In class we considered quantum tunneling of a particle of energy Eo through a barrier of...
(III) Quantum Tunneling Consider an electron in 1D in presence of a potential barrier of width L represented by a step function ſo I<0 or 1>L V U. r>0 and 2<L The total wavefunction is subject to the time-independent Schrödinger equation = EV (2) 2m ar2 +V where E is the energy of the quantum particle in question and m is the mass of the quantum particle. A The total wavefunction of a free particle that enters the barrier from...
QM 30 Relating classical and quantum mechanics IV. Supplement: Highly-excited energy eigenstates A particle is in the potential well shown at right A. First, treat this problem from a purely elassical standpoint (assume the particle has enough energy to reach both regions) Give an example of a real physical situation that corresponds to this potential well. 1. region I | region II 2. In which region of the well would the particle have greater kinetic energy? Explain. 3. In which...
6. (20pts) Consider a particle of mass m and energy E approaching the step potential V(x) = { 0x< V.>0 x > 0 from negative values of x. Consider the case E> Vo. a) Classically, what is the probability of reflection? b) Quantum mechanically, what is the probability of reflection? Express your result in terms of the ratio VIE. What is the probability of reflection if E= 2Vo?
Consider a particle encountering a barrier with potential U = U.>0 between x = -a and x = a with incoming energy E > U. a) Write the symbolic wave functions before and after passing through the barrier (i.e., for x<-a and x>a; regions I and III). U1 b) Write down the Schrodinger equation for the wave function in the middle (region II) where the potential is non-zero i.e., where -a<x<a; region II). c) What solution would you try for...
Scattering #1 Consider the "downstep" potential shown. A particle of mass m and energy E, incident from the left, strikes a potential energy drop-off of depth Vo 0 (2 pts) Using classical physics, consider a particle incident with speed vo. Use conservation of energy to find the speed on the right vf. ALSO, what is the probability that a given particle will "transmit" from the left side to the right side (again, classically)? A. B. (4 pts) This problem is...
need help with this problem. please explain, thank you. 8. Consider a particle encountering a barrier with potential U = U, >0 between x = -a and x = a with incoming energy E > U. a) Write the symbolic wave functions before and after passing through the barrier (i.e., for xs-a and x>a; regions I and III). UN b) Write down the Schrodinger equation for the wave function in the middle (region II) where the potential is non-zero i.e.,...
Problem 16.1 P16.1 In this problem, you will calculate the transmission probability through the barrier illustrated in Figure 16.10. We first go through the mathematics leading to the solution. You will then carry out further calculations. The domain in which the calculation is carried out is divided into three regions for which the potentials are Aetikx + Be-ikx Region I ψ(x)-cexpFPWh-x] - 1 V(x) =0 for x 0 V(x) = Vo for 0 < x < a V(x) =0 for...
0 Figure 2: The potential barrier setup for Problem 4 4. (10 points) "Burrowing a hole in the wall" Some particles of mass m and energy E move from the left to the potential barrier shown in Figure 2 below 0 <0 Uo 20 U(x) where Uo is some positive value (a) (5 points) Write the Time-Independent Schrödinger equations and the physically acceptable general solutions for the wave function (x) in regions I and II as labeled in Figure 2...
In class we looked at the example of the potential energy step seen below (where E > U_0). We wrote down the wave functions in complex exponential form as seen below: psi _0 (x) = A' e^i K_0 x + B' e^-i K_0 x x < 0 psi _1 (x) = C' e^i K_1 x + D' e^-i K_1 x x > 0 a) Assume the particles are incident on the barrier from the left, which coefficient can be set...
3.12.2 We perform an experiment in which we prepare a particle in a given quantum mechanical stat e and then measure the momentum of the particle. We repeat this experiment many times and obtain an average result for the momentum (p) (the expectation value of the momennum) For each of the following quantum mechanical states, give the (vector) value of (p) or, if appropriate. (p(t), where ris the time after the preparation of the state. (i) ψ(r)ocexp(ik-r (i) a particle...