Hafnia-yttria-alumina-silica based optical fibers with diminished mid-IR (>2 µm) loss

Abstract

Fabrication details and basic characteristics of a set of novel multimode hafniayttria-alumina-silicate (HYAS) core-glass based fibers, one of which is co-doped with bismuth (Bi), for the mid-IR (> 2 µm) spectral range are reported. It is demonstrated that fibers of this type possess low fundamental loss in the spectral range beyond 2 µm, lowered by fewer times as compared to conventional silica-based ones, even at moderate (units of mol.%) co-doping with hafnium. This makes them attractive for versatile mid-IR applications. Furthermore, HYAS core-glass fiber co-doped with Bi is revealed to have all the signs of 'active' (fluorescing) Bi-related centers, thus being suitable for lasing/amplifying in the near-IR spectral range.

Bismuth-doped hafnia-yttria-alumina-silica based fiber: spectral characterization in NIR to mid-IR

“…at λ~2.4 µm), lower fundamental loss than it is characteristic for Hf-free silica fibers. This advantage, already reported, has been established to originate from co-doping with HfO2 [38].…”

“…The final over-cladded HYAS-BDF has 125.0/2.9-µm clad/core diameters and numerical aperture (NA) of 0.24. Note that its version without over-cladding with 125.0/11.1-µm clad/core diameters has been studied in [38].…”

“…The other point to mention is that both Hf co-doped fibers ('A' and 'C') (a) demonstrate less in magnitude overall loss beyond 2 µm than the ones free from Hf doping ('B' and 'D') (b). This is another advantage of Hf-doping: fibers of HYAS type demonstrate significant reduction of 'fundamental' loss in mid-IR, as stated in [38] on the example of multimode HYAS-based fibers.…”

Gain‐flattened hybrid EDFA operating in C + L band with parallel pumping distribution technique

“…These fibres allow high Er 3+ ions concentration that prevents cluster formation [28] and minimise the EDF length to fulfil an ultra‐compact amplifier device [29–31]. Recently, hafnium‐bismuth‐based erbium co‐doped fibres (HB‐EDFs) have received considerable attention for the third transmission window applications [32, 33]. The choice of hafnium (Hf) ions coordinated to more than four oxygen atoms and the creation of non‐bridging oxygens in silica network cause the glass to be able to host other optically active co‐dopants materials in near‐ and mid‐infrared regions (such as erbium (Er), aluminium (Al), ytterbium (Yb), bismuth (Bi) etc.)…”

PEG-400 Destekli Alumina Sentezi, Karakterizasyonu ve Morfolojik Özelliklerin İncelenmesi

“…Alümina, mekanik, elektriksel, termal ve optik özellikleri nedeniyle endüstriyel kimyada kullanılan en önemli inorganik maddelerden biridir [1]. Sahip olduğu üstün özelliklerinden dolayı kataliz, katalizör yatağı uygulamaları, yüzey kaplamaları, refrakter madde üretimi, optik ve lazerler gibi pek çok önemli uygulamada kullanılmaktadır [2][3][4]. Alümina kristal yapılarına göre genel olarak iki grupta toplanabilir.…”