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Yang T, Liu H, Wu F, Chen H, Wang Q, Wei Z, Zhang J. Self-started Kerr-lens mode-locked thin-disk oscillator. OPTICS LETTERS 2023; 48:4633-4636. [PMID: 37656573 DOI: 10.1364/ol.495730] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/17/2023] [Accepted: 08/04/2023] [Indexed: 09/03/2023]
Abstract
Kerr-lens mode-locking (KLM) has been widely used in thin-disk oscillators to generate high-power femtosecond pulses. Here we demonstrate a Kerr-lens mode-locked Yb:YAG thin-disk oscillator that can be self-started under two configurations. The first can deliver 13-W, 235-fs pulses at a repetition rate of 103 MHz; the second delivers 49 W at a repetition rate of 46.5 MHz, whose corresponding pulse energy of 1.05 µJ is, to the best of our knowledge, the highest energy ever obtained in self-started Kerr-lens mode-locked oscillators. A new method to initiate KLM in the form of optical perturbation in a thin-disk oscillator has also been demonstrated.
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Huang S, Rompolas P. Two-photon microscopy for intracutaneous imaging of stem cell activity in mice. Exp Dermatol 2017; 26:379-383. [PMID: 27676122 PMCID: PMC7405986 DOI: 10.1111/exd.13221] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/23/2016] [Indexed: 12/17/2022]
Abstract
The adult skin is a typical example of a highly regenerative tissue. Terminally differentiated keratinocytes are shed from the external layers of the epidermis or extruded from the skin as part of the growing hair shaft on a daily basis. These are effectively replenished through the activity of skin-resident stem cells. Precise regulation of stem cell activity is critical for normal skin homoeostasis or wound healing and irregular stem cell proliferation or differentiation can lead to skin disease. The scarcity and dynamic nature of stem cells presents a major challenge for elucidating their mechanism of action. To address this, we have recently established a system for visualizing stem cell activity, in real time or long term, in the intact skin of live mice using two-photon microscopy. The purpose of this review was to provide essential information to researchers who wish to incorporate two-photon microscopy and live imaging into their experimental toolbox for studying aspects of skin and stem biology in the mouse model. We discuss fundamental principles of the method, instrumentation and basic experimental approaches to interrogate stem cell activity in the interfollicular epidermis and hair follicle.
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Affiliation(s)
- Sixia Huang
- Department of Dermatology, Institute for Regenerative Medicine, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104 U.S.A
| | - Panteleimon Rompolas
- Department of Dermatology, Institute for Regenerative Medicine, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104 U.S.A
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Peti-Peterdi J, Burford JL, Hackl MJ. The first decade of using multiphoton microscopy for high-power kidney imaging. Am J Physiol Renal Physiol 2011; 302:F227-33. [PMID: 22031850 DOI: 10.1152/ajprenal.00561.2011] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
In this review, we highlight the major scientific breakthroughs in kidney research achieved using multiphoton microscopy (MPM) and summarize the milestones in the technological development of kidney MPM during the past 10 years. Since more and more renal laboratories invest in MPM worldwide, we discuss future directions and provide practical, useful tips and examples for the application of this still-emerging optical sectioning technology. Advantages of using MPM in various kidney preparations that range from freshly dissected individual glomeruli or the whole kidney in vitro to MPM of the intact mouse and rat kidney in vivo are reviewed. Potential combinations of MPM with micromanipulation techniques including microperfusion and micropuncture are also included. However, we emphasize the most advanced and complex, quantitative in vivo imaging applications as the ultimate use of MPM since the true mandate of this technology is to look inside intact organs in live animals and humans.
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Affiliation(s)
- János Peti-Peterdi
- Departments of Physiology and Biophysics, and Medicine, Zilkha Neurogenetic Institute, Univ. of Southern California, Los Angeles, CA 90033, USA.
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Phan TG, Bullen A. Practical intravital two‐photon microscopy for immunological research: faster, brighter, deeper. Immunol Cell Biol 2010; 88:438-44. [DOI: 10.1038/icb.2009.116] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Tri Giang Phan
- Immunology Programme, Garvan Institute of Medical Research, University of New South Wales Darlinghurst New South Wales Australia
- St Vincent's Clinical School, University of New South Wales Darlinghurst New South Wales Australia
| | - Andrew Bullen
- Department of Pathology, University of California San Francisco San Francisco CA USA
- Department of Biological Imaging Development Centre, University of California San Francisco San Francisco CA USA
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Lai M. Self-starting, self-mode-locked Ti:sapphire laser. OPTICS LETTERS 1994; 19:722-724. [PMID: 19844424 DOI: 10.1364/ol.19.000722] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Self-starting of a self-mode-locked Ti:sapphire laser has been demonstrated, without any additional elements other than those necessary for self-mode locking. This self-starting is attributed to a gain saturation lens, as with self-mode locking to a Kerr lens. I achieve the self-starting by optimizing and cascading the cavity loss modulation induced by the gain saturation lens and the Kerr lens. Stable pulses shorter than 100 fs in duration are obtained at a wavelength near 840 nm.
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Sennaroglu A, Pollock CR, Nathel H. Continuous-wave self-mode-locked operation of a femtosecond Cr(4+):YAG laser. OPTICS LETTERS 1994; 19:390-392. [PMID: 19829651 DOI: 10.1364/ol.19.000390] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Continuous-wave self-mode-locked operation of a chromium-doped YAG laser pumped by a continuous-wave Nd:YAG laser at 20 degrees C is described. We used both regenerative initiation and continuous-wave self-mode-locking techniques to generate nearly transform-limited pulses of 120-fs (FWHM) duration at 1.52 microm. The TEM(00) output power was as high as 360 mW. The output of this femtosecond source was tunable from 1.51 to 1.53 microm.
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Rizvi NH, French PM, Taylor JR, Delfyett PJ, Florez LT. Generation of pulses as short as 93 fs from self-starting femtosecond Cr:LiSrAlF(6) lasers by exploiting multiple-quantum-well absorbers. OPTICS LETTERS 1993; 18:983-985. [PMID: 19823266 DOI: 10.1364/ol.18.000983] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
A Cr:LiSrAIF(6) laser has been mode locked by using a multiple-quantum-well (MQW) absorber. With the MQW absorber inside the laser cavity, Kerr lens mode locking is initiated, yielding transform-limited pulses as short as 93 fs. Pulses of 500-fs duration have also been produced by using resonant passive mode locking with the MQW absorber in an external cavity.
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Sennaroglu A, Pollock CR, Nathel H. Generation of 48-fs pulses and measurement of crystal dispersion by using a regeneratively initiated self-mode-locked chromium-doped forsterite laser. OPTICS LETTERS 1993; 18:826-828. [PMID: 19802286 DOI: 10.1364/ol.18.000826] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
A regeneratively initiated self-mode-locked chromium-doped forsterite laser operated at 3.5 degrees C is described. By employing intracavity negative-group-velocity dispersion compensation, nearly transform-limited femtosecond pulses of 48-fs (FWHM) duration were generated with average TEM(00) output powers of 380 mW at 1.23 microm. Regenerative initiation provides improvement in the output stability and ease of operation compared with fixed-frequency acousto-optic modulators. By tuning the mode-locked laser in the range 1.21-1.26 microm, estimated values for forsterite dispersion constants have also been obtained for the first time to our knowledge. The demonstrated power and stability open the door to applications such as efficient second-harmonic generation.
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Penzkofer A, Wittmann M, Bäumler W, Petrov V. Theoretical analysis of contributions of self-phase modulation and group-velocity dispersion to femtosecond pulse generation in passive mode-locked dye lasers. APPLIED OPTICS 1992; 31:7067-7082. [PMID: 20802568 DOI: 10.1364/ao.31.007067] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
The influence of self-phase modulation (SPM) and group-velocity dispersion (GVD) on pulse development in a passive mode-locked dye laser is investigated numerically by using fast Fourier transformations. The situation of positive SPM is considered. Four regions of laser performance may be distinguished: (i) In the positive GVD region pulse broadening by GVD must be balanced by the pulse-shortening effect of the saturable absorber. (ii) In a region around zero GVD the laser is periodically self-quenching and the temporal and spectral pulse shapes change periodically similar to higher-order solitons. (iii) It follows a negative GVD region where stable pulses of smooth temporal and spectral shapes are generated similar to fundamental solitons. In this region the pulse duration is practically independent of the saturable absorber concentration, and the saturable absorber is needed mainly for background suppression. (iv) Further increasing the negative GVD, pulse broadening must be balanced by the saturable absor ber pulse shortening.
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Evans JM, Spence DE, Sibbett W, Chai BH, Miller A. 50-fs pulse generation from a self-mode-locked Cr:LiSrAlF6 laser. OPTICS LETTERS 1992; 17:1447. [PMID: 19798209 DOI: 10.1364/ol.17.001447] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
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Likamwa P, Chai BH, Miller A. Self-mode-locked Cr3+:LiCaAlF6 laser. OPTICS LETTERS 1992; 17:1438. [PMID: 19798206 DOI: 10.1364/ol.17.001438] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
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Brabec T, Spielmann C, Curley PF, Krausz F. Kerr lens mode locking. OPTICS LETTERS 1992; 17:1292-1294. [PMID: 19798161 DOI: 10.1364/ol.17.001292] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Self-focusing in conjunction with an intracavity aperture creates a power-dependent amplitude modulation in laser oscillators, which allows passive mode locking. A simple analytical formalism yields closed-form expressions for the depth of passive amplitude modulation introduced by either the spatial gain profile or a hard aperture inserted in the resonator. Design issues for this mode-locking technique are discussed.
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Liu YM, Sun KW, Prucnal PR, Lyon SA. Simple method to start and maintain self-mode-locking of a Ti:sapphire laser. OPTICS LETTERS 1992; 17:1219-1221. [PMID: 19798139 DOI: 10.1364/ol.17.001219] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
By periodically moving one of the end mirrors of a Ti:sapphire laser using a shaker, we have been able to start and maintain self-mode-locking of the laser. The resulting laser is stable over a long period with low-amplitude noise (3.3%) and low random timing jitter (4.8 ps). In addition, there is a deterministic timing variation on the order of subnanoseconds, caused by the moving mirror, which can be reduced by employing a feedback system. Pulses as short as 43 fs have been obtained.
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Seas A, Petricević V, Alfano RR. Generation of sub-100-fs pulses from a cw mode-locked chromium-doped forsterite laser. OPTICS LETTERS 1992; 17:937-939. [PMID: 19794679 DOI: 10.1364/ol.17.000937] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Generation of femtosecond pulses from a continuous-wave mode-locked chromium-doped forsterite (Cr (4+):Mg(2)SiO(4)) laser is reported. The forsterite laser was actively mode locked by using an acousto-optic modulator operating at 78 MHz with two Brewster high-dispersion glass prisms for intracavity chirp compensation. Transform-limited sub-100-fs pulses were routinely generated in the TEM(00) mode with 85 mW of continuous power (with 1% output coupler), tunable over 1230-1280 nm. The shortest pulses had a 60-fs pulse width.
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Brabec T, Spielmann C, Krausz F. Limits of pulse shortening in solitary lasers. OPTICS LETTERS 1992; 17:748-750. [PMID: 19794618 DOI: 10.1364/ol.17.000748] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
The influence of dispersive pulse-broadening effects on femtosecond pulse formation in solid-state lasers has been investigated. Empirical formulas are derived from computer simulations, which permits the estimation of the magnitude of performance-limiting effects in practical solid-state systems.
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Kuo JC, Shieh JM, Hwang CD, Chang CS, Pan CL, Wu KH. Pulse-forming dynamics of a cw passively mode-locked Ti:sapphire/DDI laser. OPTICS LETTERS 1992; 17:334-336. [PMID: 19784319 DOI: 10.1364/ol.17.000334] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
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Rizvi NH, French PM, Taylor JR. Continuously self-mode-locked Ti:sapphire laser that produces sub-50-fs pulses. OPTICS LETTERS 1992; 17:279-281. [PMID: 19784301 DOI: 10.1364/ol.17.000279] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
An external cavity coupled to a dispersion-compensated, self-mode-locked Ti:sapphire laser is shown to maintain cw mode locking to produce pulses as short as 47 fs. The same cavity arrangement is also shown to generate transform-limited pulses of 2-ps duration in the regime of linear external cavity mode locking.
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Miller A, Likamwa P, Chai BH, Van Stryland EW. Generation of 150-fs tunable pulses in Cr:LiSrAlF6. OPTICS LETTERS 1992; 17:195-197. [PMID: 19784273 DOI: 10.1364/ol.17.000195] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
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