论文标题
两光子Minflux具有两倍的定位精度
Two-photon MINFLUX with doubled localization precision
论文作者
论文摘要
通过分子精度实现定位已引起人们对将荧光显微镜扩展到纳米镜检查的极大兴趣。 Minflux先驱者通过点扩展功能（PSF）工程进行了这种过渡，但其性能主要受信噪比的限制。在这里，我们证明，将两光子激发施加到MINFLUX将其本地化精度通过非线性效应的精度增加一倍。研究了Cramér-rao绑定（CRB）作为最大定位精度，并且在所有三个维度中，与单光子Minflux相比，两光子Minflux的CRB减半。同时，为了实现单光子Minflux的相同定位精度，两光子Minflux仅需要1/4的荧光光子，这导致了可能的4倍时间分辨率。可以从双光励元激发，无登记的多色纳米镜检查和超快跟踪中受益。 MINFLUX的定位精度也可以使用二阶拉瓜仪梁的激发来加倍，但与单光子和两光子的一阶Minflux相比，荧光背景高。
Achieving localization with molecular precision has been of great interest for extending fluorescence microscopy to nanoscopy. MINFLUX pioneers this transition through point spread function (PSF) engineering, yet its performance is primarily limited by the signal-to-background ratio. Here we demonstrate that applying two-photon excitation to MINFLUX would double its localization precision through PSF engineering by nonlinear effect. Cramér-Rao Bound (CRB) is studied as the maximum localization precision, and CRB of two-photon MINFLUX is halved compared to single-photon MINFLUX in all three dimensions. Meanwhile, in order to achieve same localization precision with single-photon MINFLUX, two-photon MINFLUX requires only 1/4 of fluorescence photons, contributing to a possible 4-fold temporal resolution. Benefitted from two-photon excitation, registration-free multicolor nanoscopy and ultrafast color tracking can be achieved. Localization precision of MINFLUX can also be doubled using excitation with second-order Laguerre-Gaussian beams but would suffer from high fluorescence background compared to single-photon and two-photon first-order MINFLUX.
