Abstract: A sensing system for monitoring a composition of a downhole fluid in a well, where the sensing system includes: a light source, an optical waveguide, an evanescent field sensing element that is indirect contact with a downhole fluid, and a detector. The light source is operable for emitting a beam and includes a frequency comb generator configured to modify at least a portion of the beam into a sensing comb beam. The evanescent field sensing element provides attenuated internal reflection of the sensing comb beam at the interface between the evanescent field sensing element and the downhole fluid, and the portion of the sensing comb beam interacts with the fluid to form at least a portion of an interacted beam. The detector obtains a spectral distribution of the interacted beam.

Abstract: An optical fiber has corrugations on an outer surface to dissipate a portion of an input light beam, allowing the remaining portion of the light beam to be coupled to the optical fiber. By dissipating the portion of input light, damage to the optical fiber by uncoupled light is reduced.

Abstract: Some implementations of the present disclosure provide a method that includes: irradiating a target surface with a process beam during a drilling process; in response to irradiating with the process beam, receiving a signal beam that contains light scattered from the target surface as well as light radiating from the target surface; splitting the signal beam into a first portion on a polarization arm and a second portion on a non-polarization arm; performing, on the polarization arm, a first plurality of polarization-dependent intensity and spectrum measurements of the first portion; performing, on the non-polarization arm, a second plurality of intensity and spectrum measurements of the second portion; and based on applying one or more machine learning techniques to at least portions of (i) the first plurality of polarization-dependent intensity and spectrum measurements, and (ii) the second plurality of intensity and spectrum measurements, determining a classification of the target surface.

Abstract: A laser system for freeing downhole equipment includes a laser tool having an inner diameter larger than an outer diameter of the downhole equipment and a means for generating a ring-shaped collimated laser beam. The laser system further includes a work string with the inner diameter larger than the outer diameter of the downhole equipment. The laser tool is installed on the work string and the work string is lowered around the downhole equipment. Upon lowering the work string to a position in which the laser tool is located proximate to an obstruction of the downhole tool, the laser tool emits the ring-shaped collimated laser beam so as to clear out an annulus space between the downhole equipment and a wellbore wall in order to free the downhole equipment.

Abstract: An optical fiber includes an optical fiber core for high-power laser transmission, an optical cladding disposed radially around the optical fiber core, and at least one harvesting cell disposed axially along the optical fiber core, the harvesting cell including an anode surrounding the optical cladding, a photovoltaic layer having a polymer-based photovoltaic material disposed radially around and electrically connected to the anode, and a cathode disposed radially around the photovoltaic layer and electrically connected to the photovoltaic layer.

Abstract: An optical fiber has an optical fiber core for high-power laser transmission, an optical cladding surrounding the optical fiber core, and at least one harvesting cell disposed around the optical cladding, where the harvesting cell includes an anode, a thermoelectric layer disposed adjacent to and electrically connected to the anode, and a cathode disposed adjacent to and electrically connected to the thermoelectric layer, and where the thermoelectric layer includes a polymer-based thermoelectric material.

Abstract: An example laser system includes one or more optical transmission media that are part of an optical path originating at a laser generator configured to generate an input laser beam. The example laser system includes an analyzer for receiving the input laser beam and for characterizing at least a profile and energy of the input laser beam. The example laser system includes a circulator for receiving the input laser beam from the analyzer and for minimizing or eliminating reflections. The example laser system includes a beam transformer for receiving the input laser beam from the circulator and for altering at least one property of the input laser beam thereby generating an output laser beam. The example laser system includes a writing head for altering at least one optical property of the beam transformer.

Abstract: An example method includes stimulating a wellbore using a plasma tool configured to operate in the wellbore. The method includes introducing the plasma tool into the wellbore and generating one or more first laser beams. The method includes directing the one or more first laser beams to one or more first points outside of the downhole unit and inside a volume of fluid at least partially confined by an acoustic mirror. The one or more first laser beams may create a plasma bubble at a first point resulting in one or more shock waves in the volume of fluid. The method includes deforming the acoustic mirror to produce, from the one or more shock waves, one or more destructive reflected waves directed to one or more second points outside of the downhole unit.

Abstract: An example plasma tool is configured to operate within a wellbore of a hydrocarbon-bearing rock formation. The plasma tool includes a laser head that includes one or more optical components. The laser head is configured to receive one or more laser beams at the one or more optical components and to output the one or more laser beams via the one or more optical components. The plasma tool includes a laser beam generator to generate the one or more laser beams. The laser beam is configured to induce a plasma in a volume of fluid. The plasma is for producing shock waves in the volume of fluid. The plasma tool includes a deformable acoustic mirror that confines the volume of fluid at least in part. The deformable acoustic mirror is configured to receive the shock waves to produce destructive reflected waves in the volume of fluid.

Abstract: A fiber optic cable assembly includes an elongate housing, a signal fiber placed inside the housing and extending longitudinally, and a plurality of sensing fibers placed inside the housing and extending longitudinally. The plurality of sensing fibers is placed around the signal fiber. Each of the plurality of sensing fibers carries a respective laser signal of a distinct frequency. The signal fiber carries one or more evanescent coupling signals responsive to the laser signals in the plurality of sensing fibers.

Abstract: A fiber optic cable assembly includes an elongate housing, a signal fiber placed inside the housing and extending longitudinally, and a plurality of sensing fibers placed inside the housing and extending longitudinally. The plurality of sensing fibers is placed around the signal fiber. Each of the plurality of sensing fibers carries a respective laser signal of a distinct frequency. The signal fiber carries one or more evanescent coupling signals responsive to the laser signals in the plurality of sensing fibers.

Abstract: An example method includes stimulating a wellbore using a plasma tool configured to operate in the wellbore. The method includes introducing the plasma tool into the wellbore and generating one or more first laser beams. The method includes directing the one or more first laser beams to one or more first points outside of the downhole unit and inside a volume of fluid at least partially confined by an acoustic mirror. The one or more first laser beams may create a plasma bubble at a first point resulting in one or more shock waves in the volume of fluid. The method includes deforming the acoustic mirror to produce, from the one or more shock waves, one or more destructive reflected waves directed to one or more second points outside of the downhole unit.

Abstract: An example plasma tool is configured to operate within a wellbore of a hydrocarbon-bearing rock formation. The plasma tool includes a laser head that includes one or more optical components. The laser head is configured to receive one or more laser beams at the one or more optical components and to output the one or more laser beams via the one or more optical components. The plasma tool includes a laser beam generator to generate the one or more laser beams. The laser beam is configured to induce a plasma in a volume of fluid. The plasma is for producing shock waves in the volume of fluid. The plasma tool includes a deformable acoustic mirror that confines the volume of fluid at least in part. The deformable acoustic mirror is configured to receive the shock waves to produce destructive reflected waves in the volume of fluid.

Abstract: A fiber optic cable assembly includes an elongate housing, a signal fiber placed inside the housing and extending longitudinally, and a plurality of sensing fibers placed inside the housing and extending longitudinally. The plurality of sensing fibers is placed around the signal fiber. Each of the plurality of sensing fibers carries a respective laser signal of a distinct frequency. The signal fiber carries one or more evanescent coupling signals responsive to the laser signals in the plurality of sensing fibers.

Abstract: A fiber optic cable assembly includes an elongate housing, a signal fiber placed inside the housing and extending longitudinally, and a plurality of sensing fibers placed inside the housing and extending longitudinally. The plurality of sensing fibers is placed around the signal fiber. Each of the plurality of sensing fibers carries a respective laser signal of a distinct frequency. The signal fiber carries one or more evanescent coupling signals responsive to the laser signals in the plurality of sensing fibers.

Abstract: A fiber optic cable assembly includes an elongate housing, a signal fiber placed inside the housing and extending longitudinally, and a plurality of sensing fibers placed inside the housing and extending longitudinally. The plurality of sensing fibers is placed around the signal fiber. Each of the plurality of sensing fibers carries a respective laser signal of a distinct frequency. The signal fiber carries one or more evanescent coupling signals responsive to the laser signals in the plurality of sensing fibers.

Abstract: A fiber optic cable assembly includes an elongate housing, a signal fiber placed inside the housing and extending longitudinally, and a plurality of sensing fibers placed inside the housing and extending longitudinally. The plurality of sensing fibers is placed around the signal fiber. Each of the plurality of sensing fibers carries a respective laser signal of a distinct frequency. The signal fiber carries one or more evanescent coupling signals responsive to the laser signals in the plurality of sensing fibers.