TY  - JOUR
T1  - Optical Characterization and Comparative Investigation of Cylindrical and Spherical Optical Microcavities
TT  - Silindirik ve Küresel Optik Mikrokovukların Karakterizasyonunun İncelenmesi ve Karşılaştırılması
AU  - Dündar, Gökçe
AU  - Anar, Kerem
AU  - Akçay, Namık
AU  - Eryürek, Mustafa
PY  - 2025
DA  - June
Y2  - 2025
DO  - 10.29002/asujse.1650656
JF  - Aksaray University Journal of Science and Engineering
JO  - Aksaray J. Sci. Eng.
PB  - Aksaray University
WT  - DergiPark
SN  - 2587-1277
SP  - 35
EP  - 44
VL  - 9
IS  - 1
LA  - en
AB  - This study focuses on the optical excitation and characterization of cylindrical and spherical microcavities using tapered optical fibers. Optical microcavity technologies offer significant potential for optical sensing applications requiring ultra-high sensitivity. In this study, the interaction mechanisms between tapered fiber structures and microcavities were examined in detail, and the properties of so-called “whispering gallery mode” (WGM) resonances were analyzed. Cylindrical microcavities provide a sensitive sensing platform against environmental changes due to their simple geometric structures, while spherical microcavities stand out with their symmetrical shapes and higher quality factors (Q-factors). These structures play a critical role in enhancing spectral resolution and achieving precise measurements in optical sensing. In the experimental setup, adiabatic tapering techniques were employed to fabricate tapered optical fibers, and the efficiency of fiber-microcavity interactions was optimized. This setup allowed for resolving WGMs spectrally making precise measurement of Q-factors possible. Larger free spectral ranges (FSR) were obtained with cylindrical microcavities, whereas spherical microcavities achieved extremely high Q-factors with denser mode spectra. The results revealed the critical impact of geometric properties, fabrication quality, and alignment precision of microcavities on optical performance. This study provides a significant foundation for the integration of tapered fiber-based microcavities into advanced sensing technologies. In the future, optimizing fabrication techniques and system geometries could further enhance the sensitivity and performance of microcavities.
KW  - Optical microcavity
KW  - Free spectral range (FSR)
KW  - Quality factor (Q-factor)
KW  - Whispering gallery mode (WGM)
KW  - Tapered fiber
N2  - Bu çalışma, inceltilmiş optik fiberler kullanılarak silindirik ve küresel mikrokovukların optik uyarımı ve karakterizasyonuna odaklanmaktadır. Optik mikrokovuk teknolojileri, çok yüksek hassasiyet gerektiren optik algılama uygulamalarında önemli bir potansiyel sunmaktadır. Bu çalışmada, inceltilmiş fiber yapıların mikrokovuklarla etkileşim mekanizmaları detaylı bir şekilde incelenmiş ve rezonans modlarının (WGM) özellikleri çözülmüştür. Silindirik mikrokovuklar, basit geometrik yapıları sayesinde çevresel değişikliklere karşı duyarlı bir algılama platformu sunarken, küresel mikrokovuklar şekilsel simetrileri ve daha yüksek Q-faktörleri ile öne çıkmaktadır. Bu yapılar, optik algılamada spektral çözünürlüğü arttırmak ve daha hassas ölçümler yapmak için kritik bir rol oynar.  Deneysel düzenekte, inceltilmiş optik fiberlerin üretiminde adyabatik inceltme teknikleri kullanılmış ve fiber-mikrokovuk etkileşiminin verimliliği optimize edilmiştir. Bu düzenek, hem rezonans modlarının çözülmesine hem de Q-faktörünün hassas bir şekilde ölçülmesine olanak tanımıştır. Silindirik mikrokovuklarda daha büyük serbest spektral aralıklar (FSR) elde edilirken, küresel mikrokovuklar daha yoğun mod spektrumları ile çok yüksek Q-faktörlerine ulaşmıştır.  Sonuçlar, mikrorezonatörlerin geometrik özellikleri, üretim kalitesi ve hizalama hassasiyetinin optik performans üzerindeki kritik etkisini ortaya koymuştur. Bu çalışma, inceltilmiş fiber tabanlı mikrokovukların ileri algılama teknolojilerine entegrasyonu için önemli bir temel sunmaktadır. Gelecekte, üretim tekniklerinin ve system geometrilerinin optimize edilmesi ile mikrokovukların duyarlılığını ve performansını daha da artırmak mümkün olabilecektir.
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UR  - https://doi.org/10.29002/asujse.1650656
L1  - https://dergipark.org.tr/en/download/article-file/4658053
ER  -