Name: fabrication of 1-d photonic crystal cavity on a nanofiber using femtosecond laser-induced ablation
Uploaded: 2017-02-25T13:00:00
Description: Watch this Scientific Journal Video about Fabrication of 1-D Photonic Crystal Cavity on a Nanofiber Using Femtosecond Laser-induced Ablation at JoVE.com

This work was supported by the Japan Science and Technology Agency (JST) through the Strategic Innovation Program. KPN acknowledges support from a grant-in-aid for scientific research (Grant no. 15H05462) from the Japan Society for the Promotion of Science (JSPS).

CAUTION: Wear safety glasses and strictly avoid direct exposure to UV lamp and all lasers including the femtosecond laser. Wear a clean room suit and gloves to avoid contamination. Dispose any fiber trash properly in the designated trash box.
1. Nanofiber Preparation
<ol>
	<li>Use a fiber coating stripper to strip the polymer jacket of the single mode optical fiber for a length of 5 mm at two places separated by 200 mm. Clean the two mechanically stripped parts using cleanroom wipe dipped in...

<ol>
	<li>Painter, O. J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Two-Dimensional+Photonic+Band-Gap+Defect+Mode+Laser.">Two-Dimensional Photonic Band-Gap Defect Mode Laser.</a> Science. 284, 1819-1821 (1999).</li><li>Loncar, M., Scherer, A., Qiu, Y. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Photonic+crystal+laser+sources+for+chemical+detection.">Photonic crystal laser sources for chemical detection.</a> Appl. Phys. Lett. 82, 4648 (2003).</li><li>Tanabe, T., Notomi, M., Mitsugi, S., Shinya, A., Kuramochi, E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=All-optical+switches+on+a+silicon+chip+realized+using+photonic+crystal+nanocavities.">All-optical switches on a silicon chip realized using photonic crystal nanocavities.</a> Appl. Phys. Lett. 87, 151112 (2005).</li><li>Yoshie, T., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Vacuum+Rabi+splitting+with+a+single+quantum+dot+in+a+photonic+crystal+nanocavity.">Vacuum Rabi splitting with a single quantum dot in a photonic crystal nanocavity.</a> Nature. 432, 200-203 (2004).</li><li>Akimov, A. V., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Generation+of+single+optical+plasmons+in+metallic+nanowires+coupled+to+quantum+dots.">Generation of single optical plasmons in metallic nanowires coupled to quantum dots.</a> Nature. 450, 402-406 (2007).</li><li>Noginov, M. A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Demonstration+of+a+spaser-based+nanolaser.">Demonstration of a spaser-based nanolaser.</a> Nature. 460, 1110-1112 (2009).</li><li>Zhang, X. Y., Zhang, T., Hu, A., Song, Y. J., Duley, W. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Controllable+plasmonic+antennas+with+ultra+narrow+bandwidth+based+on+silver+nano-flags.">Controllable plasmonic antennas with ultra narrow bandwidth based on silver nano-flags.</a> Appl. Phys. Lett. 101, 153118 (2012).</li><li>Tong, L., Zi, F., Guo, X., Lou, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Optical+microfibers+and+nanofibers:+A+tutorial.">Optical microfibers and nanofibers: A tutorial.</a> Opt. Comm. 285, 4641-4647 (2012).</li><li>Morrissey, M. J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Spectroscopy,+manipulation+and+trapping+of+neutral+atoms,+molecules,+and+other+particles+using+optical+nanofibers:+A+review.">Spectroscopy, manipulation and trapping of neutral atoms, molecules, and other particles using optical nanofibers: A review.</a> Sensors. 13, 10449-10481 (2013).</li><li>Kien, F. L., Dutta Gupta, S., Balykin, V. I., Hakuta, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Spontaneous+emission+of+a+cesium+atom+near+a+nanofiber:+Efficient+coupling+of+light+to+guided+modes.">Spontaneous emission of a cesium atom near a nanofiber: Efficient coupling of light to guided modes.</a> Phys. Rev. A. 72, 032509 (2005).</li><li>Nayak, K. P., Melentiev, P. N., Morinaga, M., Kien, F. L., Balykin, V. I., Hakuta, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Optical+nanofiber+as+an+efficient+tool+for+manipulating+and+probing+atomic+fluorescence.">Optical nanofiber as an efficient tool for manipulating and probing atomic fluorescence.</a> Opt. Express. 15, 5431-5438 (2007).</li><li>Nayak, K. P., Hakuta, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Single+atoms+on+an+optical+nanofiber.">Single atoms on an optical nanofiber.</a> New J. Phys. 10, 053003 (2008).</li><li>Nayak, K. P., Kien, F. L., Morinaga, M., Hakuta, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Antibunching+and+bunching+of+photons+in+resonance+fluorescence+from+a+few+atoms+into+guided+modes+of+an+optical+nanofiber.">Antibunching and bunching of photons in resonance fluorescence from a few atoms into guided modes of an optical nanofiber.</a> Phys. Rev. A. 79, 021801 (2009).</li><li>Yalla, R., Nayak, K. P., Hakuta, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Fluorescence+photon+measurements+from+single+quantum+dots+on+an+optical+nanofiber.">Fluorescence photon measurements from single quantum dots on an optical nanofiber.</a> Opt. Express. 20, 2932-2941 (2012).</li><li>Yalla, R., Kien, F. L., Morinaga, M., Hakuta, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Efficient+Channeling+of+Fluorescence+Photons+from+Single+Quantum+Dots+into+Guided+Modes+of+Optical+Nanofiber.">Efficient Channeling of Fluorescence Photons from Single Quantum Dots into Guided Modes of Optical Nanofiber.</a> Phys. Rev. Lett. 109, 063602 (2012).</li><li>Kien, F. L., Hakuta, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cavity-enhanced+channeling+of+emission+from+an+atom+into+a+nanofiber.">Cavity-enhanced channeling of emission from an atom into a nanofiber.</a> Phys. Rev. A. 80, 053826 (2009).</li><li>Kato, S., Aoki, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Strong+coupling+between+a+trapped+single+atom+and+an+all-fiber+cavity.">Strong coupling between a trapped single atom and an all-fiber cavity.</a> Phys. Rev. Lett. 115, 093603 (2015).</li><li>Hoffman, J. E., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Ultrahigh+transmission+optical+nanofibers.">Ultrahigh transmission optical nanofibers.</a> AIP Advances. 4, 067124 (2014).</li><li>Nayak, K. P., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cavity+formation+on+an+optical+nanofiber+using+focused+ion+beam+milling+technique.">Cavity formation on an optical nanofiber using focused ion beam milling technique.</a> Opt. Express. 19, 14040-14050 (2011).</li><li>Kien, F. L., Nayak, K. P., Hakuta, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Nanofibers+with+Bragg+gratings+from+equidistant+holes.">Nanofibers with Bragg gratings from equidistant holes.</a> J. Modern Opt. 59, 274-286 (2012).</li><li>Nayak, K. P., Hakuta, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Photonic+crystal+formation+on+optical+nanofibers+using+femtosecond+laser+ablation+technique.">Photonic crystal formation on optical nanofibers using femtosecond laser ablation technique.</a> Opt. Express. 21, 2480-2490 (2013).</li><li>Nayak, K. P., Zhang, P., Hakuta, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Optical+nanofiber-based+photonic+crystal+cavity.">Optical nanofiber-based photonic crystal cavity.</a> Opt. Lett. 39, 232-235 (2014).</li><li>Becker, M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Fiber+Bragg+grating+inscription+combining+DUV+sub-picosecond+laser+pulses+and+two-beam+interferometry.">Fiber Bragg grating inscription combining DUV sub-picosecond laser pulses and two-beam interferometry.</a> Opt. Express. 16, 19169-19178 (2008).</li></ol>

The lensing effect of the nanofiber plays an important role in the fabrication technique, thereby creating nano-craters on the shadow surface of the nanofiber (shown in Figure 2). The lensing effect of the nanofiber also makes the fabrication process robust to any mechanical instabilities in the transverse direction (Y-axis). Moreover, due to single-shot irradiation, the instabilities along the other axes do not affect the fabrication as the irradiation time is only 120 fs (i.e. pulse width). As...

Strong confinement of light in nanophotonic devices has opened new frontiers in optical science. Modern nanofabrication technologies have enabled fabrication of 1-D and 2-D Photonic Crystal (PhC) cavities for new prospects in lasing1, sensing2 and optical switching applications3. Moreover, strong light-matter interaction in these PhC cavities has opened new avenues for quantum information science4. Apart from PhC cavities, plasmonic nanocavities have also shown promising prospects5,6,7. However, interfacing such cavities to fiber-based communication network remains a challenge.
In recent years, tapered single mode optical fiber with subwavelength diameter, known as optical nanofiber, has emerged as a promising nanophotonic device. Due to the strong transverse confinement of the nanofiber guided field and the ability to interact with the surrounding medium, the nanofiber is widely adapted and investigated for various nanophotonic applications8. Apart from that, it is also strongly investigated and implemented for quantum manipulation of light and matter9. Efficient coupling of emission from quantum emitters like, single/few laser-cooled atoms and single quantum dots, into the nanofiber guided modes has been studied and demonstrated10,11,12,13,14,15. The light-matter interaction on nanofiber can be significantly improved by implementing PhC cavity structure on the nanofiber16,17.
The key advantage for such a system is the fiber-in-line technology which can be readily integrated to communication network. Light transmission of 99.95% through the tapered nanofiber has been demonstrated18. However, the nanofiber transmission is extremely susceptible to dust and contamination. Therefore, fabrication of PhC structure on nanofiber using conventional nanofabrication technique is not very fruitful. Although cavity fabrication on nanofiber using Focused Ion Beam (FIB) milling has been demonstrated19,20, the optical quality and reproducibility is not as high.
In this video protocol, we present a recently demonstrated21,22 technique to fabricate PhC cavities on nanofiber using femtosecond laser ablation. The fabrications are performed by creating a two-beam interference pattern of the femtosecond laser on the nanofiber and irradiating a single femtosecond laser pulse. The lensing effect of the nanofiber plays an important role in the feasibility of such techniques, creating ablation craters on the shadow surface of the nanofiber. For a typical sample, periodic nano-craters with a period of 350 nm and with diameter gradually varying from 50 - 250 nm over a length of 1 mm are fabricated on a nanofiber with diameter around 450 - 550 nm. Such periodic nano-craters on nanofiber, act as a 1-D PhC. We also present a method to control the profile of the nano-crater array to fabricate apodized and defect-induced PhC cavities on the nanofiber.
A key aspect of such nanofabrication is the all optical fabrication, so that high optical quality can be maintained. Moreover, the fabrication is done by the irradiation of just a single femtosecond laser pulse, making the technique immune to mechanical instabilities and other fabrication imperfections. Also this enables in-house production of PhC nanofiber cavity so that the probability of contamination can be minimized. This protocol is intended to help others implement and adapt this new type of nanofabrication technique.
Figure 1a shows the schematic diagram of the fabrication setup. The details of the fabrication setup and alignment procedures are discussed in21,22. A femtosecond laser with 400 nm center wavelength and 120 fs pulse width is incident on a phase mask. The phase mask splits the femtosecond laser beam in to 0 and &#177;1 orders. A beam block is used to block the 0-order beam. The folding mirrors symmetrically recombine the &#177;1-orders at the nanofiber position, to create an interference pattern. The pitch of the phase mask is 700 nm, so the interference pattern has a pitch (&#923;G) of 350 nm. The cylindrical lens focuses the femtosecond laser beam along the nanofiber. The beam size across (Y-axis) and along (Z-axis) the nanofiber is 60 &#181;m and 5.6 mm, respectively. The tapered fiber is mounted on a holder equipped with piezo actuator (PZT) for stretching the fiber. A top cover with glass plate is used to protect the nanofiber from dust. The holder with the tapered fiber is fixed on a fabrication bench equipped with translation (XYZ) and rotation (&#952;) stages. The &#952;-stage allows rotation of the nanofiber sample in the YZ-plane. The X-stage can also control the tilt angles along XY- and XZ-plane. A CCD camera is placed at a distance of 20 cm from the nanofiber and at an angle of 45&#176;&#160;in the XY-plane to monitor the nanofiber position. All the experiments are performed inside a clean booth equipped with HEPA (High-efficiency particulate arresting) filters to achieve dust-free conditions. Dust-free condition is essential to maintain the transmission of the nanofiber.
Figure 1b shows the schematic of the optical measurements. During fabrication, the optical properties are briefly monitored by launching a broadband (wavelength range: 700 - 900 nm) fiber-coupled light source into the tapered fiber and measuring the spectrum of the transmitted and reflected light using high resolution spectrum analyzer. A tunable CW laser source is used to properly resolve the cavity modes and to measure the absolute cavity transmission.
We present the protocol for the fabrication and characterization. The protocol section is divided in three subsections, nanofiber preparation, femtosecond laser fabrication and characterization of the fabricated samples.

<table border="0" cellpadding="0" cellspacing="0" width="828">
	<tbody>
		<tr height="22">
			<td height="22" style="height:22px;width:309px;">Femtosecond Laser</td>
			<td style="width:219px;">Coherent Inc.</td>
			<td style="width:236px;">Libra HE</td>
			<td style="width:64px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Phase Mask</td>
			<td>Ibsen Photonics</td>
			<td>Custom Made</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Optial Nanofiber Manufacturing Equipment&#160;&#160;</td>
			<td>Ishihara Sangyo</td>
			<td>ONME</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">ADC Card</td>
			<td>PicoTech</td>
			<td>ADC-24</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Single mode fiber</td>
			<td>Fujikura</td>
			<td>FutureGuide-SM</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Broadband source</td>
			<td>NKT Photonics</td>
			<td>SuperK EXTREME</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">CW Tunable Laser</td>
			<td>Coherent Inc.</td>
			<td>MBR-110</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Spectrum analyser (Transmission spectrum)</td>
			<td>Thermo Fisher Scientific</td>
			<td>Nicolet 8700</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Spectrum analyser (Reflection spectrum)</td>
			<td>Ocean Optics</td>
			<td>QE65000</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">CCD Camera</td>
			<td>Thorlabs</td>
			<td>DCC1545M</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Power Meter</td>
			<td>Thorlabs</td>
			<td>D3MM</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Pt-Coater</td>
			<td>Vacuum Device Inc.</td>
			<td>MSP-1S</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Scanning Electron Microscope</td>
			<td>Keyence</td>
			<td>VE-9800</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">UV Curable Epoxy</td>
			<td>NTT-AT</td>
			<td>AT8105</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Photodiode</td>
			<td>ThorLabs</td>
			<td>PDA 36A-EC</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Clean room wipe</td>
			<td>TExWipe</td>
			<td>TX-404</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Fiber coating stripper</td>
			<td>NTT-AT</td>
			<td>Fiber nippers 250 &#956;m&#160;</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Cover glass</td>
			<td>Matsunami Glass IND,LTD</td>
			<td>NEO micro cover glass 0.12-0.17 mm&#160;</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">PZT</td>
			<td>NOLIAC</td>
			<td>NAC 2011-H20</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Cylindrical lens stage</td>
			<td>NewPort</td>
			<td>M-481-A&#160;</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Y,Z stages</td>
			<td>Chuo Precision Industrial Co., LTD.</td>
			<td>LD-149-C7</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Rotation stage</td>
			<td>SIGMA KOKI</td>
			<td>KSPB-1026MH</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Z-stage(1), Z-stage(2)</td>
			<td>NewPort</td>
			<td>M-460P&#160;</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Fiber coating stripper</td>
			<td>NTT-AT</td>
			<td>Fiber nippers 250 &#956;m&#160;</td>
			<td></td>
		</tr>
	</tbody>
</table>

fabrication of 1-d photonic crystal cavity on a nanofiber using femtosecond laser-induced ablation

We present a protocol for fabricating 1-D Photonic Crystal (PhC) cavities on subwavelength-diameter tapered optical fibers, optical nanofibers, using femtosecond laser-induced ablation. We show that thousands of periodic nano-craters are fabricated on an optical nanofiber by irradiating with just a single femtosecond laser pulse. For a typical sample, periodic nano-craters with a period of 350 nm and with diameter gradually varying from 50 - 250 nm over a length of 1 mm are fabricated on a nanofiber with diameter around 450 - 550 nm. A key aspect of such a nanofabrication is that the nanofiber itself acts as a cylindrical lens and focuses the femtosecond laser beam on its shadow surface. Moreover, the single-shot fabrication makes it immune to mechanical instabilities and other fabrication imperfections. Such periodic nano-craters on nanofiber, act as a 1-D PhC and enable strong and broadband reflection while maintaining the high transmission out of the stopband. We also present a method to control the profile of the nano-crater array to fabricate apodized and defect-induced PhC cavities on the nanofiber. The strong confinement of the field, both transverse and longitudinal, in the nanofiber-based PhC cavities and the efficient integration to the fiber networks, may open new possibilities for nanophotonic applications and quantum information science.

Figure 2 shows the SEM image of a typical segment of the fabricated nanofiber sample. It shows that periodic nano-craters are formed on the shadow side of the nanofiber, with a periodicity of 350 nm corresponding well to the interference pattern. The inset shows the enlarged view of the sample. The shape of the nano-craters is almost circular and the diameter of a typical nano-crater is around 210 nm.
Fi...

Watch this Scientific Journal Video about Fabrication of 1-D Photonic Crystal Cavity on a Nanofiber Using Femtosecond Laser-induced Ablation at JoVE.com

Fabrication of 1-D Photonic Crystal Cavity on a Nanofiber Using Femtosecond Laser-induced Ablation

We present a protocol for fabricating 1-D photonic crystal cavities on subwavelength diameter silica fibers (optical nanofibers) using femtosecond laser-induced ablation.

We present a protocol for fabricating 1-D Photonic Crystal (PhC) cavities on subwavelength-diameter tapered optical fibers, optical nanofibers, using ...

Research

JoVE Journal

Engineering

Fabrication And Characterization Of Photonic Crystal Slow Light Waveguides And Cavities

Slow light has been one of the hot topics in the photonics community in the past decade, generating great interest both from a fundamental point of view ...

Measurement of Coherence Decay in GaMnAs Using Femtosecond Four-wave Mixing

The application of femtosecond four-wave mixing to the study of fundamental properties of diluted magnetic semiconductors ((s,p)-d hybridization, ...

Using Microwave and Macroscopic Samples of Dielectric Solids to Study the Photonic Properties of Disordered Photonic Bandgap Materials

Recently, disordered photonic materials have been suggested as an alternative to periodic crystals for the formation of a complete photonic bandgap (PBG). ...

Laser-induced Forward Transfer for Flip-chip Packaging of Single Dies

Flip-chip (FC) packaging is a key technology for realizing high performance, ultra-miniaturized and high-density circuits in the micro-electronics ...

Laser-induced Forward Transfer of Ag Nanopaste

Over the past decade, there has been much development of non-lithographic methods1-3 for printing metallic inks or other functional materials. Many of ...

Resonance Fluorescence of an InGaAs Quantum Dot in a Planar Cavity Using Orthogonal Excitation and Detection

The ability to perform simultaneous resonant excitation and fluorescence detection is important for quantum optical measurements of quantum dots (QDs). ...

Preparation of Large-area Vertical 2D Crystal Hetero-structures Through the Sulfurization of Transition Metal Films for Device Fabrication

We have demonstrated that through the sulfurization of transition metal films such as molybdenum (Mo) and tungsten (W), large-area and uniform transition ...

A Fabrication and Measurement Method for a Flexible Ferroelectric Element Based on Van Der Waals Heteroepitaxy

Flexible non-volatile memories have received much attention as they are applicable for portable smart electronic device in the future, relying on ...

Fabrication of Magnetic Nanostructures on Silicon Nitride Membranes for Magnetic Vortex Studies Using Transmission Microscopy Techniques

Electron and x-ray magnetic microscopies allow for high-resolution magnetic imaging down to tens of nanometers. However, the samples need to be prepared ...

Quantitative Analysis of Vacuum Induction Melting by Laser-induced Breakdown Spectroscopy

Vacuum induction melting is a popular method for refining high purity metal and alloys. Traditionally, standard process control in metallurgy involves ...