Sub-100 fs pulses from an all-polarization maintaining Yb-fiber oscillator with an anomalous dispersion higher-order-mode fiber

Verhoef, A. J.; Zhu, Long; Israelsen, Stine Møller; Grüner-Nielsen, L.; Unterhuber, Angelika; Kautek, Wolfgang; Rottwitt, Karsten; Baltuška, Andrius; Fernández, A.

doi:10.1364/oe.23.026139

Cited by 14 publications

(5 citation statements)

References 13 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The optical setup (see Figure 1 ) used to image the sorghum kernels is similar to the setup reported by Sen et al [ 30 ] but was modified to increase the measurement speed more than 1000-fold. Illumination is provided by an all-polarization-maintaining femtosecond Yb-doped fiber oscillator [ 33 ] emitting at a central wavelength of 1030 nm. A fiber collimator L1 (Thorlabs F240APC-1064) is used to couple the oscillator output into a polarization-maintaining single-mode fiber (PM-SMF).…”

Section: Methodsmentioning

confidence: 99%

“…A fiber collimator L1 (Thorlabs F240APC-1064) is used to couple the oscillator output into a polarization-maintaining single-mode fiber (PM-SMF). This PM-SMF is spliced onto the single-mode pigtail of a higher-order-mode (HOM) fiber, which can support four modes, including the Bessel-like LP 02 mode [ 33 , 34 , 35 ]. Mode conversion from the fundamental LP 01 mode to the LP 02 mode is achieved through long-period grating with a period Λ matching the difference in the propagation constant

of the LP 01 and LP 02 modes, which was written into the HOM fiber core using ultraviolet radiation.…”

Section: Methodsmentioning

confidence: 99%

See 1 more Smart Citation

Non-Destructive Direct Pericarp Thickness Measurement of Sorghum Kernels Using Extended-Focus Optical Coherence Microscopy

Sen

Fernández

Crozier

et al. 2023

Sensors

View full text Add to dashboard Cite

Non-destructive measurements of internal morphological structures in plant materials such as seeds are of high interest in agricultural research. The estimation of pericarp thickness is important to understand the grain quality and storage stability of seeds and can play a crucial role in improving crop yield. In this study, we demonstrate the applicability of fiber-based Bessel beam Fourier domain (FD) optical coherence microscopy (OCM) with a nearly constant high lateral resolution maintained at over ~400 µm for direct non-invasive measurement of the pericarp thickness of two different sorghum genotypes. Whereas measurements based on axial profiles need additional knowledge of the pericarp refractive index, en-face views allow for direct distance measurements. We directly determine pericarp thickness from lateral sections with a 3 µm resolution by taking the width of the signal corresponding to the pericarp at the 1/e threshold. These measurements enable differentiation of the two genotypes with 100% accuracy. We find that trading image resolution for acquisition speed and view size reduces the classification accuracy. Average pericarp thicknesses of 74 µm (thick phenotype) and 43 µm (thin phenotype) are obtained from high-resolution lateral sections, and are in good agreement with previously reported measurements of the same genotypes. Extracting the morphological features of plant seeds using Bessel beam FD-OCM is expected to provide valuable information to the food processing industry and plant breeding programs.

show abstract

Section: Methodsmentioning

confidence: 99%

of the LP 01 and LP 02 modes, which was written into the HOM fiber core using ultraviolet radiation.…”

Section: Methodsmentioning

confidence: 99%

Non-Destructive Direct Pericarp Thickness Measurement of Sorghum Kernels Using Extended-Focus Optical Coherence Microscopy

Sen

Fernández

Crozier

et al. 2023

Sensors

View full text Add to dashboard Cite

show abstract

“…A scheme of the experimental setup is shown in Figure 1 . The laser source for the experiments was a home-built femtosecond Ytterbium-doped fiber laser oscillator, designed according to [ 31 ]. The output of the laser cavity was directed to a pair of diffraction gratings that compensate the dispersion and compress the laser pulse.…”

Section: Methodsmentioning

confidence: 99%

“…In the present study, apertureless scanning probe near-field lithography was employed to write nanofeatures on the surface of gold films. A home-built femtosecond Ytterbium-doped fiber laser oscillator based on a novel design [ 31 ] was applied. A repetition rate of 46 MHz and a low pulse energy was chosen to allow a better thermomechanical equilibrium of the cantilever in contrast to laser sources with kHz repetition rates and higher energy per pulse [ 30 ].…”

Section: Introductionmentioning

confidence: 99%

Subwavelength Nanostructuring of Gold Films by Apertureless Scanning Probe Lithography Assisted by a Femtosecond Fiber Laser Oscillator

Casas

Kautek

2018

Nanomaterials

View full text Add to dashboard Cite

Optical methods in nanolithography have been traditionally limited by Abbe’s diffraction limit. One method able to overcome this barrier is apertureless scanning probe lithography assisted by laser. This technique has demonstrated surface nanostructuring below the diffraction limit. In this study, we demonstrate how a femtosecond Yb-doped fiber laser oscillator running at high repetition rate of 46 MHz and a pulse duration of 150 fs can serve as the laser source for near-field nanolithography. Subwavelength features were generated on the surface of gold films down to a linewidth of 10 nm. The near-field enhancement in this apertureless scanning probe lithography setup could be determined experimentally for the first time. Simulations were in good agreement with the experiments. This result supports near-field tip-enhancement as the major physical mechanisms responsible for the nanostructuring.

show abstract

“…Broadband mode conversion have several applications e.g. within group velocity dispersion (GVD) compensation [1][2][3] which may be used in ultrashort pulsed lasers [4,5], but also within sensing [6]. The ability to achieve a broader and tailorable conversion bandwidth is thus highly desirable.…”

Section: Introductionmentioning

confidence: 99%

Broadband higher order mode conversion using chirped microbend long period gratings

Israelsen

Rottwitt

2016

Opt. Express

View full text Add to dashboard Cite

Abstract:We suggest a new scheme to create chirped microbend long period gratings. Employing this scheme, the bandwidth of mode conversion between LP 01 to LP 11 is increased 4.8-fold with a conversion efficiency of 20 dB. This scheme includes a first time demonstration of a nonlinearly chirped long period grating. The scheme is investigated both numerically using coupled mode equations as well as experimentally.

show abstract

Sub-100 fs pulses from an all-polarization maintaining Yb-fiber oscillator with an anomalous dispersion higher-order-mode fiber

Cited by 14 publications

References 13 publications

Non-Destructive Direct Pericarp Thickness Measurement of Sorghum Kernels Using Extended-Focus Optical Coherence Microscopy

Non-Destructive Direct Pericarp Thickness Measurement of Sorghum Kernels Using Extended-Focus Optical Coherence Microscopy

Subwavelength Nanostructuring of Gold Films by Apertureless Scanning Probe Lithography Assisted by a Femtosecond Fiber Laser Oscillator

Broadband higher order mode conversion using chirped microbend long period gratings

Contact Info

Product

Resources

About