'''Quantum defect''' may refer to:
* Quantum defect (lasers), an unavoidable inefficiency in laser beam generation * The effective nuclear charge correction in hydrogen-like Rydberg atoms
{{disambig}}
'''Quantum defect''' may refer to:
* Quantum defect (lasers), an unavoidable inefficiency in laser beam generation * The effective nuclear charge correction in hydrogen-like Rydberg atoms
{{disambig}}