9. Y. Lee, D. Djukic, R. M. Roth, R. Laibowitz, T. Izuhara, R. M. Osgood, Jr., S. Bakhru, H. Bakhru, W. Si, and D. Welch, “Fabrication of patterned single-crystal SrTiO3 thin films by ion slicing and anodic bonding,” App. Phys. Lett. 89(12), 122902, 2006.
A
new technique for directly fabricating patterned thin films (<1 μm
thick) of fully single-crystal strontium titanate uses deep H+ implantation
into the oxide sample, followed by anodic bonding of the sample to a Pyrex or
Pyrex-on-Si substrate. The dielectric properties and crystal structure of such
thin films are characterized and are found to be essentially those of the bulk
single-crystal.
8. R. M. Roth, D. Djukic, Y. Lee, R. M. Osgood, Jr., S. Bakhru, B. Laulicht, K. Dunn, H. Bakhru, L. Wu, and M. Haung, “Compositional and structural changes in LiNbO3 following deep He+ ion implantation for film exfoliation,” App. Phys. Lett. 89(11), 112906, 2006.
The
physical mechanism of He-ion-based exfoliation in Z-cut LiNbO3 is
investigated. Rutherford
backscattering/channeling, nuclear-reaction analysis, and transmission electron
microscopy are used to examine the compositional and structural changes caused
by deep ion implantation followed by thermal annealing. Lattice disruption,
He-bubble formation, and Li depletion are observed in the implantation region,
as well as the onset of exfoliation. The implications of these observations for
the crystal ion slicing method are discussed.
7. R. M. Roth, N.-C. Panoiu, M. M. Adams, R. M. Osgood, Jr., C. C. Neacsu, and M. B. Raschke, “Resonant-plasmon field enhancement from asymmetrically illuminated conical metallic-probe tips,” Optics Express, 14(7), 2921-2931, 2006. Also featured in The Virtual Journal for Biomedical Optics 1(5), 2006. Also featured in The Virtual Journal for Biological Physics Research 11(10), 2006.
Optical-field
enhancement and confinement for an asymmetrically illuminated nanoscopic Au tip
suspended over a planar Au substrate is investigated both numerically and
experimentally. The spatial field distribution of the tip-sample system was
calculated using the full 3D finite-difference time-domain method. The
calculation enables investigation of the effects of the substrate-tip
placement, angle of incidence, and spectral response. The tip plasmon response
leads to a significant (up to ∼70
times) local field enhancement between the tip and substrate. The enhancement
is found to be extremely sensitive to the tip-sample separation distance.
Tip-enhanced Raman scattering experiments were performed and the numerical
results provide a consistent description of the observed field localization and
enhancement.
6. R. M. Roth, T. Izuhara, R. L. Espinola, D. Djukic, R. M. Osgood, Jr., S. Bakhru, and H. Bakhru, “Compact and integrable wide-free-spectral-range Fabry-Perot optical filters fabricated from freestanding LiNbO3 thin films,” Optics Lett., 30(9), 994, 2005.
In this letter we demonstrate the first use of freestanding thin films of lithium niobate for the purpose of chip-scale integrated optical filtering. The films are produced by means of Crystal Ion Slicing; this process exfoliates a microns-thin layer of single-crystal optical material from a bulk parent by means of high-energy ion implantation. In this case, 10μm thick films of Z-cut lithium niobate were fabricated, coated on each side with a silver mirror layer, and then integrated into a silica-on-silicon waveguide block. Because of their thin nature, these filters have a very large free-spectral-range, exceeding 6.78THz (>50nm at 1550nm), and use very little chip area when integrated.
5. David W. Ward, Eric Statz, Keith A. Nelson, Ryan M. Roth, and Richard M. Osgood, Jr., “THz wave generations and propagation in thin film LiNbO3 produced by crystal ion slicing.” App. Phys. Lett., 86, 022908, 2005.
Terahertz phonon-polariton generation and real-space imaging with femtosecond optical pulses are demonstrated in a 10-μm thick film of single crystalline lithium niobate that was generated through crystal ion slicing. The film dispersion properties were characterized throughout the polariton wavelength range of 5-100 μm, revealing slab waveguide behavior at the longer wavelengths.
4. D. Djukic, R. Roth, J. T. Yardley, R. M. Osgood, Jr., S. Bakhru, and H. Bakhru, “Low-voltage planar-waveguide electooptic prism scanner in Crystal-Ion-Sliced thin-film LiNbO3.” Optics Express. 12(25), 6159, 2004.
We report on the use of thin, i.e. 10 µm-thick, single-crystal LiNbO3, in low-voltage electrooptic prism scanners. These devices are fabricated by electric-field poling of a series of electrooptic prisms in a bulk crystal followed by high-energy ion implantation and subsequent etching of the poled samples. Such a single-crystal thin-film scanner, while having the same scanning functionality as with a bulk device, has an order-of-magnitude reduction in its required voltage; for example, a series of two prisms, of 2mm in total length, yields a deflection angle of 0.7 at 100V compared to more than 1.7kV for the same device in standard 200 µm-thick LiNbO3 wafers.
3. T. Izuhara, R. Roth, R.M. Osgood, Jr., S. Bakhru, and H. Bakhru, “Low-voltage tunable TE/TM convertor on ion-sliced lithium niobate thin film.” Electronics Lett., 39(15), 1118-1119, 2003.
Lift-off of a prefabricated thin-film lithium niobate device using ion slicing has been demonstrated. The device is a low-voltage electrooptically tunable TE/TM mode converter, which is fabricated on a sliced 10 micron-thick film. A new electrode configuration allows this thin-film device low-voltage tuning of the mode conversion wavelength at 0.26 nm/V. the high tuning per volt is attributed to an improved overlap integral in the thin-film form of the device.
2. M. Purschke, S. Adler, E. Desmond, L. Ewell, J. Haggerty, H. Kehayias, R. Roth, C. Witzig and S. Pate, “The PHENIX Online Computing System.” IEEE Transactions on Nuclear Science, 47(2), 51-55, 2000.
The Online Computing System (ONCS) is responsible for the overall configuration and control of the PHENIX detector system. The experiment is made up of 4 spectrometer arms with a total number of 11 subdetectors, which need to be operated by a single control and monitoring system. This includes the configuration of the individual components of the readout system, as well as the control of the state of the detector's data flow. Furthermore, the ONCS system sets up the environment for the online monitoring of the detectors. The slow control of the high voltages and other ancillary devices is also part of the system.
The ONCS system is designed around a distributed computing model which relies on CORBA object oriented technology, the ROOT system as the backbone of the online monitoring, and EPICS for the control of the High Voltage systems. Issues regarding the use and implementation of these technologies in the ONCS system will be discussed, as well as the methods used to control the state of the health of the PHENIX detector.
1. E. Desmond, S. Adler, L. Ewell, J. Haggerty, H. Kehayias, S. Pate, M. Purschke, R. Roth and C. Witzig, “Use of CORBA in the PHENIX Distributed Online Computing System.” IEEE Transactions on Nuclear Science, 47(2), 344-347, 2000.
The PHENIX online control system is responsible for the configuration, control, and monitoring of the PHENIX detector data acquisition system and ancillary control hardware, and the collection and archiving of the event data. The detector consists of 11 distinct subsystems, which are distributed physically and partitioned logically while ultimately being combined into a single operating unit. The online system consists of a large number of embedded commercial and custom processors as well as custom software processes which are involved in the collection, monitoring and control of the detector over a diverse set of computing platforms including VME base Power PC controllers, Pentium based NT systems, and SUN Solaris SPARC processors. CORBA has been adopted as the standard communication mechanism for PHENIX online system. This paper will describe the design, implementation and use of CORBA to achieve a uniform and platform independent control environment while providing for the access, control and monitoring of the online detector elements over the distributed and diverse control environment. Synchronous and asynchronous communication issues will be discussed as well as the development of CORBA compliant components that were developed to achieve client/server isolation and deterministic system behavior. The use and interaction between JAVA based clients and C++ based CORBA servers to further achieve a platform neutral environment will be presented.
13. R.
M. Roth, N.-C. Panoiu, M. M. Adams, J. Dadap, R. M. Osgood, Jr., J.
Warren, and A. Stein, “Plasmonic Crosses: Polarization-Sensitive Extraordinary
Transmission through Periodic Arrays of Crossed Nano-Slits Mediated by Local
Surface Plasmons,” Frontiers in Optics (OSA Annual Meeting, The Optical
Society of America; Rochester, NY; October 8-12, 2006). Invited as an encore presentation,
presented during the Best of Topicals special symposia.
12. R. M. Roth, N.-C. Panoiu, M. M. Adams, and R. M. Osgood, “Plasmon-Resonant Field Enhancement Metallic Tip-Substrate Systems.” Poster, Conference on Lasers & Electro-Optics (CLEO, The Optical Society of America; Long Beach, CA; May 21-26, 2006), JWB101.
Optical
field enhancement (~70x) for light incident on a nanoscopic Au probe tip
suspended over a Au substrate is investigated numerically. The spectral
response and effect of system geometry are examined using 3D-FDTD.
11. D. Djukic, R. M. Roth, R. M. Osgood, Jr., K. Evans-Lutterodt, D. Welch, S. Bakhru, H. Bakhru, “Patterned Regions of Thin Single-Crystal Functional Oxides (LiNbO3) by Localized He+ Ion-Implantation: Material Properties.” Poster, 2006 Joint NSLS and CFN Users’ Meeting (Brookhaven National Laboratory; Upton, NY; May 15-17, 2006)
We demonstrate the
polarization-dependant, local-plasmon-enhanced transmission characteristics of
light incident on a periodic array of customized, nanoscale cruciform patterns.
These characteristics are simulated; the patterns are fabricated on Au and Ag
films using electron-beam lithography.
9. R. M. Roth, D. Djukic, R. M. Osgood, Jr., S. Bakhru, and H. Bakhru, “Ion-beam probing of He+ and H+ ion-sliced LiNbO3 and SrTiO3,” MRS Fall Meeting (Boston, MA; November 28 – December 2, 2005), T9.7.
Crystal
Ion Slicing (CIS) is a technique that uses ion implantation and subsequent
thermal treatment and etching to exfoliate thin, single-crystalline films from
the surface of a bulk metal-oxide crystal, such as lithium niobate. CIS has
been used to create new optical devices, such as integrated optical filters,
low-voltage scanners and polarization converters, etc. The performance of these
devices was enhanced relative to their bulk crystal counterparts through the
use of CIS single-crystal thin films. In addition, it has been shown that the
CIS process can produce high-quality films of variable thickness for a wide
variety of other oxide optical materials, including LiNbO3, LiTaO3,
KTaO3, YIG, BaTiO3, and SrTiO3.
Despite its great utility, there has been a relatively small effort to characterize the materials physics of the process, including the distribution and mobility of the ion-implanted species in the presence of low-temperature annealing/processing. Such a heat treatment is needed to enhance the exfoliation process and after exfoliation to eliminate any stress within the film. Precise control of crystalline stress is crucial to developing large films without fractures, particularly for the case of very thin films (<1μm), and to achieving high-quality electrical and optical properties. In this paper, we present an investigation of the implanted ion-distribution, ion-induced defects, and any chemical changes induced by shallow He+ or H+ ion implantation in LiNbO3 and SrTiO3. The change in these quantities as a result of annealing was also investigated. This study was conducted using ion beam analysis techniques, including Rutherford Backscattering (RBS) and Nuclear Reaction Analysis (NRA), conducted at the Ion Beam Laboratory at SUNY. In particular, NRA is extremely useful in providing a detailed profile of specific atomic concentrations within implanted samples and can be used to directly observe the composition of the implanted ion layer. Transmission electron microscopy and atomic force microscopy have also been used to examine local stress and surface morphology after implantation. After being analyzed, heat treatment and etching techniques were used to exfoliate the thin films; once sliced, these films were examined with optical techniques, AFM, SEM, TEM, and additional ion beam analysis to determine the film quality and residual ion concentration.
8. Y.
S. Lee, D. Djukic, R. M. Roth, R. M. Osgood, Jr., S. Bakhru, and H.
Bakhru, “Characteristics of thin ion-sliced bonded SrTiO3 thin
films,” Poster. MRS Fall Meeting (Boston,
MA; November 28 – December 2, 2005), T10.20.
7. D.Djukic, R. M. Roth, R. M. Osgood, Jr., K. Evans-Lutterodt, H. Bakhru, and S. Bakhru, “Optical and Structural Properties of Patterned Regions of Thin Single-Crystal Films of LiNbO3 Fabricated by Localized He+ Ion-Implantation,” MRS Fall Meeting (Boston, MA; November 28 – December 2, 2005), T3.50.
6. Djordje Djukic, Tomoyuki Izuhara, R. M. Roth, R. L. Espinola, Richard M. Osgood, Jr., Sasha Bakhru, and Hassaram Bakhru, “Extremely thin, Single-Crystal Films of LiNbO3 Fabricated Using localized He+ Ion-Implantation,” Conference on Lasers & Electro-Optics (CLEO, The Optical Society of America; Baltimore, MD; May 22-27, 2005), CMN3.
We demonstrate that extremely thin, i.e., ~2-3 um, single-crystal films of LiNbO3 can be formed on a wafer using patterned ion-implantation followed by chemical etching. Control of the membrane thickness and its waveguiding properties are demonstrated.
5. Djordje Djukic, R. M. Roth, James T. Yardley, Richard M. Osgood, Jr., Sasha Bakhru, and Hassaram Bakhru, “10x Voltage Reduction in an Electrooptic Prism Scanner in Thin-Film LiNbO3 Using Crystal Ion Slicing,” Conference on Lasers & Electro-Optics (CLEO, The Optical Society of America; Baltimore, MD; May 22-27, 2005), CTuW5.
We demonstrate a
10x reduction in the driving voltage of an electrooptical scanner in LiNbO3. The
scanner is made by exfoliating a 10um thick crystal slab off the surface of a
bulk device using Crystal Ion Slicing.
4. R. M. Osgood, Jr., R. M. Roth, T. Izuhara, D. Djukic, R. L. Espinola, M. Bahl, J. I. Dadap, and N.-C. Panoiu, “New Materials Technologies for Ultracompact Photonics,” in the 49th Annual Meeting of the SPIE(Denver, CO; August 2-6, 2004), 5554-21 Session5. [INVITED]
New metal and metal-composite-based optical materials structures are emerging, which can push the fundamental limits imposed by diffraction to dimensions of < 10th the wavelength of light. These structures are characterized by large local field enhancement, as a result of the excitation of surface plasmon waves or localized plasmon resonances at the surface of the metal. In this talk we describe the optical properties of these materials as well as devices incorporating these materials. Our work uses rigorous numerical simulation as well as experimental measurements. This work has shown that, while periodic metallic structures share many of the properties of dielectric photonic crystals, there are significant differences such as the existence of nearly flat bands with highly reduced group-velocity dispersion, bands that are associated with plasmon modes, or the significant field enhancement mentioned above. Further, we discuss several new strategies for fabricating materials and devices using self-assembly and optical-field driven growth, which enables growth of shaped nanoscale metallic features. New fabrication methods for thin single-crystal films with also be presented.
3. T. Izuhara, Djordje Djukic, R. M. Roth, Richard M. Osgood, Jr., Sasha Bakhru, and Hassaram Bakhru, “Integrated components using single-crystal thin-film LiNbO3”, Integrated Photonics Research Topical Meeting (IPR, The Optical Society of America; San Francisco, CA; June 27 – July 2, 2004), IFF1.
Crystal ion slicing can be used to fabricate single-crystal, microns-thick, complex-oxide thin-films for fundamentally new, integrated optic devices and structures. Using this technique, we have routinely sliced the thin-films of lithium niobate, one of the important electro-optical materials. The film thickness can be tuned from sub-micron to 10-microns. Here we describe the technology and device applications focusing on the ion-sliced lithium niobate thin-films. Demonstrated devices include electrically tunable filter, electro-optical beam scanner, Fabry-Perot filter, and very thin waveguides.
2. Ryan M. Roth, Tomoyuki Izuhara, Djordje Djukic, Richard M. Osgood, Jr., Sasha Bakhru, and Hassaram Bakhru, “Integrable, wide free-spectral-range Fabry-Perot filters fabricated from freestanding LiNbO3 thin films.” Conference on Lasers & Electro-Optics (CLEO, The Optical Society of America; San Francisco, CA; May 16-21, 2004), CThMM2.
Fabry-Perot filters possessing free-spectral-ranges in excess of 50 nanometers (6.78 THz) have been demonstrated in 10-micron thin freestanding lithium niobate. The ultra-compact form of the filters enables integration into optical waveguide systems.
1. T. Izuhara, R. M. Roth, R. M. Osgood, Jr., M. Fay, and J. M. Xu, “Multiwavelength TE/TM convertors on titanium in-diffused lithium niobate using binary superimposed gratings.” Optical Society of America Annual Meeting (Orlando, FL; Sept. 29 – Oct 3, 2002), TuK4.
Binary sumperimposed gratings are fabricated as electrodes on titanium in-diffused waveguides to realize tunable multiwavelength TE/TM converters. The mode index difference between the TE and TM modes allows larger grating structures, which are formed by direct laser writing. Tolerance to fabrication error is investigated using analytical and computational methods.
Media Articles and Press Releases
1. Ion-sliced Single-crystal LiNbO3 Thin Films and Their Applications, IEEE LEOS Newsletter, vol. 18(4), p. 4, August 2004.