55 research outputs found
Unidimensional Time Domain Quantum Optics
Choosing the right first quantization basis in quantum optics is critical for
the interpretation of experimental results. The usual frequency basis is, for
instance, inappropriate for short, subcycle waveforms. Deriving first
quantization in time domain shows that the electromagnetic field is not
directly proportional, nor even causally related, to the photonic field (the
amplitude probability of a photon detection). We derive the relation between
the two and calculate the statistics of the electromagnetic field for specific
states in time domain, such as the single photon Fock state. We introduce the
dual of the Hamiltonian in time domain and extend the concept of quadratures to
all first quantization bases.Comment: 4 pages, 3 figures; supplementary material: 6 pages, 1 figure;
changes from version 1: discussion of results largely extende
Nonsymmetrized Correlations in Quantum Noninvasive Measurements
A long-standing problem in quantum mesoscopic physics is which operator order
corresponds to noise expressions like , where I(\omega) is
the measured current at frequency \omega. Symmetrized order describes a
classical measurement while nonsymmetrized order corresponds to a quantum
detector, e.g., one sensitive to either emission or absorption of photons. We
show that both order schemes can be embedded in quantum weak-measurement theory
taking into account measurements with memory, characterized by a memory
function which is independent of a particular experimental detection scheme. We
discuss the resulting quasiprobabilities for different detector temperatures
and how their negativity can be tested on the level of second-order correlation
functions already. Experimentally, this negativity can be related to the
squeezing of the many-body state of the transported electrons in an ac-driven
tunnel junction.Comment: 5+2 pages, 1 figur
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