{'fraction_non_alphanumeric': 0.02875399361022364, 'fraction_numerical': 0.025559105431309903, 'mean_word_length': 4.497076023391813, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Broadband Passively Mode-Locked Fiber Laser with DNA Aqueous Solution as Saturable Absorber

We demonstrate a passively mode-locked fiber laser using aqueous DNA solution as a saturable absorber (SA), with broadband pulse laser emission from 1 to 1.5 µm. The mode-locked laser with erbium-doped fiber as the gain material has a center wavelength of 1563 nm, a 3 dB bandwidth of 3.9 nm, and a pulse width of 822 fs, whereas the laser with ytterbium-doped fiber as the gain material and an identical DNA aqueous SA has a center wavelength of 1037 nm, a 3 dB bandwidth of 5.04 nm, and a pulse width of 250 ps. The proposed laser, which is simple and cost effective to fabricate, exhibits excellent long-term stability as well as thermal stability during high-power operation. This mode-locked laser scheme with a liquid-phase DNA component has the potential to provide in-depth understanding of the optical nonlinearity and usefulness of DNA.