Bad Qubits — Learn Quantum by Doing

Multiple choice

A coherent state

|\alpha\rangle

of the harmonic oscillator is defined by which property?

It is an eigenstate of the creation operator $a^\dagger$
It is an eigenstate of the Hamiltonian $H$ with a definite, sharp energy
It is an eigenstate of the annihilation operator $a$ , with $a|\alpha\rangle = \alpha|\alpha\rangle$ for a complex number $\alpha$
It is a single number state $|n\rangle$ with a fixed, definite photon number $n$