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For a system of bosons at room temperature, compute the average occupancy of a single-particle state and the probability of the state containing 0,1,2,3bosons, if the energy of the state is

(a) 0.001eVgreater than μ

(b) 0.01eVgreater than μ

(c) 0.1eVgreater than μ

(d) 1eVgreater than μ

Short Answer

Expert verified

Result is:

The energuy state is: (a).n¯=25.2

The energuy state is: (b).localid="1651000533351" n¯=2.10

The energuy state is: (c).localid="1651000556743" n¯=0.0208

The energuy state is: (d).localid="1651000583464" n¯=1.244×10-17

Step by step solution

01

Part(a) Step 1:Given information

We have been given that n¯=1e(ϵ-μ)/kT-1

02

Part(a) Step 2: Simplify

Here

P(n)=e-n(ϵ-μ)/kT1-e-(ϵ-μ)/kT

kT=8.62×10-5eV/K(298K)=0.02569eV

to find the average occupancy:

n¯=1e0.001eV/0.02569eV-1

n¯=25.2

if it contains n=1

P(1)=e-(1)(0.001eV)/0.02569eV1-e-0.001eV/0.02569eV

P(1)=0.03672

if it contains n=3

P(3)=e-(3)(0.001eV)/0.02569eV1-e-0.001eV/0.02569eV

P(3)=0.034

03

Part(b) Step 1:Given information

We have been given that ϵ-μ=0.01eV

04

Part(b) Step 2: Simplify

If it contain n=0

P(0)=e-(0)(0.01eV)/0.02569eV1-e-0.01eV/0.02569eV

P(0)=0.322

If it contains n=1

P(1)=e-(1)(0.01eV)/0.02569eV1-e-0.01eV/0.02569eV

P(1)=0.218

05

Part(c) Step 1: Given information

We have been given that ϵ-μ=0.1eV

06

Part(c) Step 2: Simplify

If it contains n=0

P(0)=e-(0)(0.1eV)/0.02569eV1-e-0.1eV/0.02569eV

P(0)=0.9796

If it contains n=1

P(1)=e-(1)(0.1eV)/0.02569eV1-e-0.1eV/0.02569eV

P(1)=0.020

07

Part(d) Step 1:Given information

We have been given that ϵ-μ=1eV

08

Part(d) Step 2: Simplify

If it contains n=0

P(0)=e-(0)(1eV)/0.02569eV1-e-1eV/0.02569eV

P(0)=1

If it contains n=1

P(1)=e-(1)(1eV)/0.02569eV1-e-1eV/0.02569eV

P(1)=1.244×10-17

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Most popular questions from this chapter

Repeat the previous problem, taking into account the two independent spin states of the electron. Now the system has two "occupied" states, one with the electron in each spin configuration. However, the chemical potential of the electron gas is also slightly different. Show that the ratio of probabilities is the same as before: The spin degeneracy cancels out of the Saha equation.

Consider any two internal states, s1 and s2, of an atom. Let s2 be the higher-energy state, so that Es2-Es1=ϵ for some positive constant. If the atom is currently in state s2, then there is a certain probability per unit time for it to spontaneously decay down to state s1, emitting a photon with energy e. This probability per unit time is called the Einstein A coefficient:

A = probability of spontaneous decay per unit time.

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