Nonclassical Radiation from Thermal Cavities in the Ultrastrong Coupling Regime

Thermal or chaotic light sources emit radiation characterized by a slightly enhanced probability of emitting photons in bunches, described by a zero-delay second-order correlation function $g^{(2)}(0) = 2$. Here we explore photon-coincidence counting statistics of thermal cavities in the ultrastrong coupling regime, where the atom-cavity coupling rate becomes comparable to the cavity resonance frequency. We find that, depending on the system temperature and coupling rate, thermal photons escaping the cavity can display very different statistical behaviors, characterised by second-order correlation functions approaching zero or greatly exceeding two.Comment: results on frequency resolved photon correlations added, to appear in Phys. Rev. Let

Photon correlations from ultra-strong optical nonlinearities

We study the full field and frequency filtered output photon statistics of a resonator in thermal equilibrium with a bath and containing an arbitrarily large quartic nonlinearity. According to the general theory of photodetection, we derive general input-output relations valid for the ultra-anharmonic regime, where the nonlinearity becomes comparable to the energy of the resonator, and show how the emission properties are modified as compared to the generally assumed simple anharmonic regime. We analyse the impact of the nonlinearity on the full statistics of the emission and its spectral properties. In particular we derive a semi-analytical expression for the frequency resolved two-photon correlations or two-photon spectrum of the system in terms of the master equation coefficients and density matrix. This provides a very clear insight into the level structure and emission possibilities of the system.Comment: 10 pages, 7 figure

CONSTRUCTING A DISABLED IDENTITY: THE INFLUENCE OF IMPAIRMENT, SOCIAL FACTORS AND REFLECTED APPRAISALS

The claiming of an identity as disabled has important implications for impaired individuals' interpersonal interactions and well-being, however not all impaired individuals claim a disabled identity. In this dissertation I build upon social and medical models of disability by extending the work in two key ways using multi-methods. First, using a symbolic interactionist frame, I examine how individuals' experiences are mediated through self processes in shaping their identity claims. Second, I assess how the identification process is influenced by individuals' social statuses. Data used in this study is from the 1994-1995 National Health Interview Survey on Disability, a large nationally representative sample of individuals with impairments. In addition, I supplement this analysis with data from 30 qualitative interviews. Results underscore prior research showing that not all individuals who experience impairment identify as disabled. The qualitative interviews illuminated a third group not obvious in the quantitative analysis - those in the process of negotiating a disabled identity. Experiences of socially constructed barriers have important implications for claiming an identity as disabled; however experiences of impairment also have strong effects on identity claims. In depth interviews also showed social barriers, but not environmental barriers, and impairment affect impaired persons' identity claims as disabled. Self-processes perform an important role in helping impaired individuals understand their positioning in society and verify their identity claims. Reflected appraisals of being disabled increased the likelihood of claiming a disabled identity and these appraisals mediated the relationship between the experiences of socially constructed barriers, impairment and the self. In the qualitative analyses, social comparisons and self presentations were also found to be an agentic tool used by individuals to assert their identities as disabled/not disabled and in shaping others' views of them. Finally, social statuses have important implications for the construction or rejection an identity as disabled. Those with higher social statuses were MORE likely to claim disabled identity, all things equal. In the qualitative analyses, women's disabled identity claims were often disregarded, perhaps underscoring their more difficult experience verifying their identity claims. Consistent with this, interactions between social statuses and the social and medical models were identified