A novel method of magnetic field assisted nondestructive optical probing of photonic lattice structures in photorefractive crystals is demonstrated experimentally. High contrast annular symmetry micrometric scale refractive lattice structures were recorded by nondiffracting Bessel beam technique with the use of 532 nm, 17 mW power laser beam in Fe doped lithium niobate crystal. The stability of recorded lattices against erasure during readout by probe Gaussian beam at the recording wavelength has been studied. Time evolutions of the diffraction efficiency of the lattices for readout beam power of 17 mW in zero magnetic field and in external magnetic field of 0.85 T were measured. The measurements showed up to 3.4 times increase of erasure constant for magnetic field assisted readout of stored lattices. The physical model based on the approach of small polarons in external magnetic field to explain the experimental results is discussed.

实验证明了一种新型的磁场辅助光折射晶体中光子晶格结构的无损光学探测方法。通过非衍射贝塞尔光束技术，在掺铁铌酸锂晶体中使用532 nm，17 mW功率激光束，记录了高对比度环形对称微米尺度的折射晶格结构。已经研究了在记录波长下由探针高斯光束在读出期间所记录的晶格对擦除的稳定性。在零磁场和0.85 T的外部磁场中，测量了读出功率为17 mW时晶格的衍射效率随时间的变化。测量结果表明，磁场辅助读取存储的晶格的擦除常数提高了3.4倍。