Efficient 1400–1600 nm Circularly Polarized Luminescence from a Tuned Chiral Erbium Complex

Novel chiral Er complexes based on both enantiomers of extended (i)PrPyBox (2,6‐Bis[4‐isopropyl‐4,5‐dihydrooxazol‐2‐yl)]pyridine) show strong near‐infrared circularly polarized luminescence (CPL) within the 1400 to 1600 nm spectral region under 450 nm irradiation. CPL activity in this region, despite being particularly rare, would open the way to potential applications in the domain, e.g., of fiber‐optic telecommunications and free‐space long‐distance optical communications employing circularly polarized light. Moreover, the long wavelength excitation is advantageous for applications in the field of (circularly polarized) microscopy and bioimaging.