Generation of a squeezed vacuum resonant on Rubidium D_1 line with periodically-poled KTiOPO_4

We report generation of a continuous-wave squeezed vacuum resonant on the Rb D_1 line (795 nm) using periodically poled KTiOPO_4 (PPKTP) crystals. With a frequency doubler and an optical parametric oscillator based on PPKTP crystals, we observed a squeezing level of -2.75 +- 0.14 dB and an anti-squeezing level of +7.00 +- 0.13 dB. This system could be utilized for demonstrating storage and retrieval of the squeezed vacuum, which is important for the ultra-precise measurement of atomic spins as well as quantum information processing.Comment: 4 pages, 4 figure

Quantum memory of a squeezed vacuum for arbitrary frequency sidebands

We have developed a quantum memory technique that is completely compatible with current quantum information processing for continuous variables of light, where arbitrary frequency sidebands of a squeezed vacuum can be stored and retrieved using bichromatic electromagnetic induced transparency. 2MHz sidebands of squeezed vacuum pulses with temporal widths of 470ns and a squeezing level of -1.78 +- 0.02dB were stored for 3us in the laser-cooled 87Rb atoms. -0.44 +- 0.02dB of squeezing was retrieved, which is the highest squeezing ever reported for a retrieved pulse.Comment: 4pages, 5figure

The bright and dark sides of emotional intelligence : implications for educational practice and better understanding of empathy

In recent years, educational practitioners have become more aware of the importance of cultivating students’ social and emotional skills, in order to facilitate adaptation beyond academic contexts. Emotional intelligence (EI), the ability to regulate one’s own and others’ emotions appropriately, has often been targeted in educational interventions. Previous studies suggest that EI promotes various positive social outcomes such as social support, prosocial behaviour, and subjective well-being. However, a growing body of research has also shown that EI may sometimes lead to antisocial behaviours such as indirect aggression and support for others’ retaliation, but this “darker side” of EI tends to be overlooked. We argue that emotional intelligence without empathy can bring about manipulative or aggressive behaviour, and highlight the need to explore further how EI interacts with other personality traits in determining different social outcomes. This review addresses both the “bright” and the “dark” side of EI, aiming to offer a comprehensive, balanced perspective on its adaptive functions. Based on Reinforcement Sensitivity Theory (RST), our paper proposes that there might be a common mechanism by which EI links to both prosociality and aggression. Our analysis leads to the conclusion that researchers need to elaborate on the motivational mechanism underlying the behaviours of emotionally intelligent individuals, while teachers would be well- advised to pay attention to the motivations that support students’ socially adaptive behaviours.peer-reviewe

Rayleigh-Taylor instability and mushroom-pattern formation in a two-component Bose-Einstein condensate

The Rayleigh-Taylor instability at the interface in an immiscible two-component Bose-Einstein condensate is investigated using the mean-field and Bogoliubov theories. Rayleigh-Taylor fingers are found to grow from the interface and mushroom patterns are formed. Quantized vortex rings and vortex lines are then generated around the mushrooms. The Rayleigh-Taylor instability and mushroom-pattern formation can be observed in a trapped system.Comment: 5 pages, 4 figure

The Physics of Galaxy Cluster Outskirts

As the largest virialized structures in the universe, galaxy clusters continue to grow and accrete matter from the cosmic web. Due to the low gas density in the outskirts of clusters, measurements are very challenging, requiring extremely sensitive telescopes across the entire electromagnetic spectrum. Observations using X-rays, the Sunyaev-Zeldovich effect, and weak lensing and galaxy distributions from the optical band, have over the last decade helped to unravel this exciting new frontier of cluster astrophysics, where the infall and virialization of matter takes place. Here, we review the current state of the art in our observational and theoretical understanding of cluster outskirts, and discuss future prospects for exploration using newly planned and proposed observatories.Comment: 56 pages. Review paper. Published in Space Science Review