Exciting polaritons with quantum light

We discuss the excitation of polaritons---strongly-coupled states of light and matter---by quantum light, instead of the usual laser or thermal excitation. As one illustration of the new horizons thus opened, we introduce Mollow spectroscopy, a theoretical concept for a spectroscopic technique that consists in scanning the output of resonance fluorescence onto an optical target, from which weak nonlinearities can be read with high precision even in strongly dissipative environments.Comment: 5 pages, 3 figure

Structure of the harmonic oscillator in the space of n-particle Glauber correlators

We map the Hilbert space of the quantum harmonic oscillator to the space of Glauber’s nth-order intensity correlators, in effect showing “the correlations between the correlators” for a random sampling of the quantum states. In particular, we show how the popular g(2) function is correlated to the mean population and how a recurrent criterion to identify single-particle states or emitters, namely, g(2)<1/2g(2)<1/2, actually identifies states with at most two particles on average. Our charting of the Hilbert space allows us to capture its structure in a simpler and physically more intuitive way that can be used to classify quantum sources by surveying which territory they can access

Ultrafast control of Rabi oscillations in a polariton condensate

We report the experimental observation and control of space and time-resolved light-matter Rabi oscillations in a microcavity. Our setup precision and the system coherence are so high that coherent control can be implemented with amplification or switching off of the oscillations and even erasing of the polariton density by optical pulses. The data is reproduced by a fundamental quantum optical model with excellent accuracy, providing new insights on the key components that rule the polariton dynamics.Comment: 5 pages, 3 figures, supplementary 7 pages, 4 figures. Supplementary videos: https://drive.google.com/folderview?id=0B0QCllnLqdyBNjlMLTdjZlNhbTQ&usp=sharin

Frequency-resolved Monte Carlo

We adapt the Quantum Monte Carlo method to the cascaded formalism of quantum optics, allowing us to simulate the emission of photons of known energy. Statistical processing of the photon clicks thus collected agrees with the theory of frequency-resolved photon correlations, extending the range of applications based on correlations of photons of prescribed energy, in particular those of a photon-counting character. We apply the technique to autocorrelations of photon streams from a two-level system under coherent and incoherent pumping, including the Mollow triplet regime where we demonstrate the direct manifestation of leapfrog processes in producing an increased rate of two-photon emission events

Estudio preliminar de la ingesta de nutrientes de niños deportistas de Sierra Nevada

A study was conducted of the diet of a child Alpine ski competition team (Monachil Club, Sierra Nevada). The children,aged between 7-12 years old, were divided into two groups. One of which were residents at a ski resort and the other,residents from different cities, who practised skiing at the same resort at weekends only.A 24-hour recall questionnaire was carried out, from which the following data was collected: The mean energy valuefrom diet intake was determined at 3,218 ± 819 Kcal/day (ski resort group) and 2,485 ± 600 Kcal/day (city group). Nosignificant differences between the groups was observed (p≥0.3). The distribution of energy from energetic nutrients wascorrect for the ski resort group, both at the weekend and during the week; the city group had an excessive intake oflipids (43%) and proteins (17%), and the energy from carbohydrates did not reach 55%. A modification in the diet andintake of energy and nutrients was observed when the children moved from their family home to the ski resortSe ha realizado un estudio de la dieta del equipo de competición infantil en esquí alpino (Club Monachil, SierraNevada). Son niños con edades entre 7-12 años. Se consideran dos grupos, los residentes en la estación de esquí ylos de ciudad que esquían en fin de semana.Se han realizado encuestas de recuerdo 24 horas. El valor medio de energía, es 3218 Kcal/dia ± 819 (grupo de lasierra) y 2485 Kcal/dia ± 600 (grupo de ciudad), no existen diferencias significativas entre grupos (p≥0,3). Ladistribución de energía a partir de los nutrientes energéticos es correcta para los niños deportistas de la sierra, tantoen el fin de semana como entre semana; los niños deportistas de ciudad tienen un consumo excesivo de lípidos (43%)y prótidos (17%), el aporte de energía de carbohidratos no llega al 55%. Se observa una modificación de la dietay del consumo de energía y nutrientes cuando los niños pasan del hogar familiar a la practica del deporte

Broad-band high-resolution rotational spectroscopy for laboratory astrophysics

We present a new experimental set-up devoted to the study of gas phase molecules and processes using broad-band high spectral resolution rotational spectroscopy. A reactor chamber is equipped with radio receivers similar to those used by radio astronomers to search for molecular emission in space. The whole range of the Q (31.5-50 GHz) and W bands (72-116.5 GHz) is available for rotational spectroscopy observations. The receivers are equipped with 16 × 2.5 GHz fast Fourier transform spectrometers with a spectral resolution of 38.14 kHz allowing the simultaneous observation of the complete Q band and one-third of the W band. The whole W band can be observed in three settings in which the Q band is always observed. Species such as CH3CN, OCS, and SO2 are detected, together with many of their isotopologues and vibrationally excited states, in very short observing times. The system permits automatic overnight observations, and integration times as long as 2.4 × 105 s have been reached. The chamber is equipped with a radiofrequency source to produce cold plasmas, and with four ultraviolet lamps to study photochemical processes. Plasmas of CH4, N2, CH3CN, NH3, O2, and H2, among other species, have been generated and the molecular products easily identified by the rotational spectrum, and via mass spectrometry and optical spectroscopy. Finally, the rotational spectrum of the lowest energy conformer of CH3CH2NHCHO (N-ethylformamide), a molecule previously characterized in microwave rotational spectroscopy, has been measured up to 116.5 GHz, allowing the accurate determination of its rotational and distortion constants and its search in space.We thank the European Research Council for funding support under Synergy Grant ERC-2013-SyG, G.A. 610256 (NANOCOSMOS). IT, VJH, and JLD acknowledge additional partial support from the Spanish State Research Agency (AEI) through grant FIS2016-77726-C3-1-P. JAMG, LM, and GS acknowledge additional partial support from the Spanish State Research Agency (AEI) through grant MAT2017-85089-C2-1R. We thank David López Romero for his help during the process of installation, commissioning, and cleaning of the chamber. We would like to thank Kremena Makasheva for the useful comments and suggestions during the experiments with Hexamethyldisiloxane. We would also like to thank Rosa Lebrón, Jesús Quintanilla, and Cristina Soria for providing us with the sample of N-ethylformamide. Sandra I. Ramírez acknowledges support from the FONCICYT under grant number 291842. Celina Bermúdez thanks the Spanish Ministerio de Ciencia Innovación y Universidades for the Juan de la Cierva grant FJCI-2016-27983

Three-dimensional photographic analysis of the face in European adults from southern Spain with normal occlusion: reference anthropometric measurements

Background: Recent non-invasive 3D photography method has been applied to facial analysis, offering numerous advantages in orthodontic. The purpose of this study was to analyze the faces of a sample of healthy European adults from southern Spain with normal occlusion in order to establish reference facial soft tissue anthropometric parameters in this specific geographic-ethnic population, as well as to analyze sexual dimorphism. Methods: A sample of 100 healthy adult volunteers consisting of 50 women (mean age, 22.92 ± 1.56 years) and 50 men (mean age, 22.37 ± 2.12 years) were enrolled in this study. All participants had normal occlusion, skeletal Class I, mesofacial pattern, and healthy body mass index. Three-dimensional photographs of the faces were captured noninvasively using Planmeca ProMax 3D ProFace®. Thirty landmarks related to the face, eyes, nose, and orolabial and chin areas were identified. Results: Male displayed higher values in all vertical and transversal dimensions, with the exception of the lower lip height. Larger differences between sexes were observed in face, mandible, and nose. Male also had higher values in the angular measurements which referred to the nose. No sex differences were found in transverse upper lip prominence or transverse mandibular prominence. No differences were found in the ratio measurements, with the exception of intercantal width/nasal width, which was higher in women than in men. Conclusions: Reference anthropometric measurements of facial soft tissues have been established in European adults from southern Spain with normal occlusion. Significant sexual dimorphism was found, with remarkable differences in size between sexe