There is, I think, something ethereal about i —the square root of minus one. I remember first hearing about it at school. It seemed an odd beast at that time—an intruder hovering on the edge of reality.

Usually familiarity dulls this sense of the bizarre, but in the case of i it was the reverse: over the years the sense of its surreal nature intensified. It seemed that it was impossible to write mathematics that described the real world in …

I and i

다중혈관 관상동맥 환자에서 y-문합을 이용하여 양쪽 내흉동맥만을 사용한 우회술의 조기 성적

抗原变异可使得多种致病微生物易于逃避宿主免疫应答。表达在感染红细胞表面的恶性疟原虫红细胞表面蛋白1（PfPMP1）与感染红细胞、内皮细胞、树突状细胞以及胎盘的单个或多个受体作用，在黏附及免疫逃避中起关键的作用。每个单倍体基因组var基因家族编码约60种成员，通过启动转录不同的var基因变异体为抗原变异提供了分子基础。

疟原虫var基因转换速率变化导致抗原变异[英]／Paul H, Robert P, Christodoulou Z, et al//Proc Natl Acad Sci U S A

[신간의 별자리x] 우리/미술, 그리고 ‘슬픔의 박물관’

Bose-Einstein condensation (BEC) has been observed in a dilute gas of sodium atoms. A Bose-Einstein condensate consists of a macroscopic population of the ground state of the system, and is a coherent state of matter. In an ideal gas, this phase transition is purely quantum-statistical. The study of BEC in weakly interacting systems which can be controlled and observed with precision holds the promise of revealing new macroscopic quantum phenomena that can be understood from first principles.

Bose-Einstein condensation in a gas of sodium atoms

Single mode emission of tapered lasers was achieved by an on-chip distributed Bragg reflector. The quantum dot based devices show stable single mode emission around 920 nm, good beam quality and output powers up to 2 W.

Single mode quantum dot tapered lasers

Efficient single photon collection is demonstrated based on a μ-fiber-coupled photonic crystal cavity. 249 kHz of single photons are detected, and estimated single photon count rate(overall collection efficiency) is 20 MHz(25 %).

/pdf/efficient-single-photon-collection-using-a-m-fiber-coupled-1qg4ovleai.pdf

Efficient single photon collection using a μ-fiber-coupled microcavity

We discuss quantum light emission from solid state single photon sources, either based on single InGaAs quantum dots or trapped excitonic complexes in monolayer WSe 2 . Embedding InGaAs quantum dots in micropillar cavities, we can simultaneously obtain high purity, bright (up to 75% extraction efficiency) and coherent emission of single photons. Single photon emission in monolayers of transition metal dichalcogenides is confirmed via second order autocorrelation measurements yielding g2(0) ∼ 0.1.

Strategies for bright single photon sources in solid state: Coupled quantum dot cavities and monolayer-based systems

We present detailed measurements of the Henry factor (linewidth enhancement factor) above and below threshold of a quantum dot laser. Modulation frequency and current dependence of the above-threshold method based on modulation experiments is shown.

Frequency dependent Henry-factor measurements of quantum dot distributed feedback lasers

We demonstrate the emission of highly indistinguishable photons from a quasi-resonantly pumped coupled quantum dot-microcavity system operating in the weak coupling regime. Furthermore we model the degree of indistinguishability with our novel microscopic theory.

/pdf/highly-indistinguishable-photons-from-a-qd-microcavity-with-qzplewd596.pdf

Sven Höfling

Papers

Single mode quantum dot tapered lasers

Efficient single photon collection using a μ-fiber-coupled microcavity

Strategies for bright single photon sources in solid state: Coupled quantum dot cavities and monolayer-based systems

Frequency dependent Henry-factor measurements of quantum dot distributed feedback lasers

Highly indistinguishable photons from a QD-microcavity with a large Purcell-factor