The Lamb shift, an energy shift arising from the presence of the electromagnetic vacuum,
has been observed in various quantum systems and established as part of the energy shift
independent of the environmental photon number. However, typical studies are based on
simplistic bosonic models which may be challenged in practical quantum devices. We
demonstrate a hybrid bosonic-fermionic environment for a linear resonator mode and
observe that the photon number in the environment can dramatically increase both the …

The Lamb shift, an energy shift arising from the presence of the electromagnetic vacuum,
has been observed in various quantum systems and established as the part of the energy
shift independent of the environmental photon number. However, typical studies are based
on simplistic bosonic models and may be challenged in practical quantum devices. We
demonstrate a hybrid bosonic-fermionic environment for a linear-resonator mode and
observe that the photon number in the environment can dramatically increase both the …