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We demonstrate simultaneous control of both the phase and amplitude of light using a conjugate gradient minimisation-based hologram calculation technique and a single phase-only spatial light modulator (SLM). A cost function, which incorporates the inner product of the light field with a chosen target field within a defined measure region, is efficiently minimised to create high fidelity patterns in the Fourier plane of the SLM. A fidelity of F = 0.999997 is achieved for a pattern resembling an LG10 mode with a calculated light-usage efficiency of 41.5%. Possible applications of our method in optical trapping and ultracold atoms are presented and we show uncorrected experimental realisation of our patterns with F = 0.97 and 7.8% light efficiency.

We propose and analyze a scheme for parametrically cooling bilayer cuprates based on the selective driving of a $c$-axis vibrational mode. The scheme exploits the vibration as a transducer making the Josephson plasma frequencies time-dependent. We show how modulation at the difference frequency between the intra- and interbilayer plasmon substantially suppresses interbilayer phase fluctuations, responsible for switching $c$-axis transport from a superconducting to resistive state. Our calculations indicate that this may provide a viable mechanism for stabilizing non-equilibrium superconductivity even above $T_c$, provided a finite pair density survives between the bilayers out of equilibrium., Comment: 4 pages + 7 page supplemental

The primary aim was to describe New Zealand secondary school students' use of dental services and determine the nature and extent of any inequities by deprivation status and ethnicity. A secondary aim was to to describe their toothbrushing practices and self-reported dental pain experience, past restorative treatment and tooth loss.Secondary analysis of data from the cross-sectional Youth 07: National Survey of the Health and Wellbeing of New Zealand Secondary School Students. A representative sample of 9,098 secondary school students aged 13-17 years from 96 secondary schools across New Zealand took part, with a response rate of 73%. Self-report information about oral health care behaviour, past dental experiences and dental visiting pattern was collected. Data analysis took the complex survey design into account, and multivariate analysis was undertaken to examine the associations of dental service-use.A dental visit in the previous 12 months was reported by 72% of participants. The odds of having done so were higher among females, those who brushed at least twice daily, and those who had been kept awake at night by dental pain. Lower odds were seen among students identifying with Māori, Pacific or Asian people (and those in the 'Other' ethnic category) than among European students, and among those residing in medium- or high-deprivation areas than those in lo-deprivation areas. One in seven participants reported having lost a tooth due to oral disease. Having had a tooth filled was reported by almost three-quarters of the sample, and having been kept awake by dental pain at night was reported by just over one in five. Almost two-thirds reported brushing their teeth twice or more in the previous 24 hours, and a small minority had not brushed at all.Ethnic and socio-economic inequities in the use of dental services are apparent among New Zealand adolescents.

We adapt the bialgebra and Hopf relations to expose internal structure in the ground state of a Hamiltonian with $Z_2$ topological order. Its tensor network description allows for exact contraction through simple diagrammatic rewrite rules. The contraction property does not depend on specifics such as geometry, but rather originates from the non-trivial algebraic properties of the constituent tensors. We then generalise the resulting tensor network from a spin-1/2 lattice to a class of exactly contractible states on spin-S degrees of freedom, yielding the most efficient tensor network description of finite Abelian lattice gauge theories. We gain a new perspective on these states as examples of two-dimensional quantum states with algebraically contractible tensor network representations. The introduction of local perturbations to the network is shown to reduce the von Neumann entropy of string-like regions, creating an unentangled sub-system within the bulk in a certain limit. We also show how perturbations induce finite-range correlations in this system. This class of tensor networks is readily translated onto any lattice, and we differentiate between the physical consequences of bipartite and non-bipartite lattices on the properties of the corresponding quantum states. We explicitly show this on the hexagonal, square, kagome and triangular lattices., Comment: 23 pages, 6 figures