Association of vertically coupled polymer micro-resonator and phase-sensitive optical low coherence interferometer for label-free biosensing applications

Abstract

We report on a new accurate investigation tool whose principle is that of a Michelson interferometer with a broadband source, namely a phase-sensitive optical low-coherence interferometer, used to interrogate an optical micro-resonator based sensor for label-free biosensing applications. This set-up, which is able to provide the amplitude and also the phase of the guided mode in a single measurement, is also used to evaluate the performances of the micro-resonators. The best vertically coupled polymer racetrack micro-resonator fabricated displays a Q-factor higher than 38 000 and a finesse of 21 at 1527.7 nm when immersed in deionized water. The association of the phase-sensitive optical low coherence interferometer and the vertically coupled polymer micro-resonator in an opto-fluidic cell for biosensing applications was tested and allowed the detection of a concentration of glucose in water solution around 0.23 mg ml−1.

Implementation and assessment of a low-cost 3D laser platform controlled by open software for printing polymeric micro-structures

“…The solution is discernible such as two-dimensional and one-dimensional patterns, which can be understood such as the product of the irradiance functions in each dimension for the square case. Attending this and considering that the irradiance of a single slit is I(x)/I(0) = sinc 2 [ πbx λD ] , the irradiance over the screen can be expressed as, I (x, y) I (0) = sinc 2 πbx λD sinc 2 πay λD (10) where a = 596 µm and b = 684 µm are the width and length, respectively, of the micro-square, and D is the distance to the screen where the pattern is projected. In order to obtain the diffraction patterns, the micro-aperture and slit were positioned perpendicular (such as transparent obstacle) to the trajectory of a He:Ne CW-laser, centered in 633 nm with 15 mW output.…”

“…By considering the diffraction irradiance expressions exposed above, the corresponding theoretical values are approximately ∼2.5 mm and ∼5.2 mm, respectively. The difference is due to the fact that equation (10) does not consider an aperture that can be transmitted through it walls, as it is in the case of the SU8 photoresist by being a transparent material, where refraction of incident light is presented. This means that light transmits through the square aperture but also through the perimeter of it, so the light that propagates within the perimeter propagates through an interface consisting of air, SU8, SLG and air again.…”

“…Complex micro-structures have received special interest in photonics [1][2][3], integrated optics [4] and nano-technology [5,6] because of the high capability to manipulate light at the micro-and sub-micrometer length scales. It has been demonstrated that polymer-based micro-structures can work as resonator cavities [7,8], integrated interferometers [9], cantilevers [10,11], molds for simple and complex micro-fluidics masks and so on [12,13]. All these important micro-structures present extraordinary advantages on photonics, biochemical sensing and plasmonic applications.…”

Low temperature PECVD processes for the fabrication of integrated symmetrical resonant UV210 organic/semiconductor structures

“…Within optical cavities, a portion of the light, known as the evanescent field, extends beyond the core of the structure, enabling interactions with the surrounding environment [8,9]. This property has been used for various purposes, including label-free detection [10][11][12][13] and the investigation of soft matter behaviors directly in contact with the resonators [14,15]. Among the various materials explored for these applications, polymer waveguides fabricated using optical lithography have emerged as a central point of research [16].…”

Interféromètre optique à faible cohérence couplé aux microrésonateurs optiques en polymère : nouveau protocole de biodétection.

“…(a) variation du temps de groupe en fonction de la concentration de glucose ; (b) variation de la sensibilité en fonction du nombre de tours de cavité.La sensibilité totale en phase obtenue pour les expériences précédentes est de -510,3 fs/(mg•mL −1 ).Lorsque nous considérons le double des écart types de reproductibilité des mesures PS-OLCI, comme étant le plus petit décalage détectable, nous obtenons une limite de détection, en termes de concentration de glucose, de 45 μg•mL −1 sur le module et de 25 μg•mL −1 sur la phase après un tour de cavité. Ces résutats montrent une limite de détection quatre fois inférieure à celle qui a été déjà publée[14]. La différence est due à l'amélioration de la valeur du facteur de qualité du microrésonnateur utilisé ici.…”