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(Solved): 3. Splitting of Energy Levels Consider a 3-D Quantum Isotropic Cartesian Simple Harmonic Oscillator ...
3. Splitting of Energy Levels Consider a 3-D Quantum Isotropic Cartesian Simple Harmonic Oscillator (SHO). Here "3-D" and "Cartesian" means that we oscillate in each of three dimensions, x,y and z. "Isotropic" means that the spring constant ? is the same value for each dimension so that U(x,y,z)=2??(x2+y2+z2). Similarly as for an infinite well, we can solve the corresponding Schrodinger equation by separation of variables, i.e ?(x,y,x)=?n1??(x)?nn??(y)?nl??(z), where nx?,ny? and nz? are non-negative integers. The corresponding energy levels are given by. En?=(nz?+ny?+nx?+23?)hw, with ?x?=?y?=?z?=?. ? (a) Explicitly determine the Energy Degeneracy associated with all states with energies corresponding to nx?+ny?+n1?=n=0,1,2,3.4. Effectively, all you need to do here is write down all of the "permutations" of the three numbers that generate the same energy for each value of n. Demonstrate that your result is consistent with the following general expression for degeneracy for a 3-D Isotropic SHO given by: Degeneracy =(n+1)(n+2)/2. (b) Suppose instead of being isotropic, the spring constants are defined as follows: ?x?=?y?=?0?, and ?z?=1.1?b?. In other words, the spring constant is ten pereent higher in the " ? " direction. Make a "quantum energy level diagram" that shows the energy levels for all states with energies En? corresponding to n=0,1,2,3. For each energy level describe the "splitting". For example, for n=1 your diagram should show that the three-fold degeneracy you found for E1? for the Isotropic SHO in Part (a) has now been split into two energy levels (one of which is two-fold degenerate). Recall that the frequency of an harmonic oscilator in terms of the spring constant in given by ?=m???. Also observe that in the 3D case, we should have in principle a frequency per each dimension x,y, and z.