<?xml version="1.0" encoding="utf-8"?><feed xmlns="http://www.w3.org/2005/Atom" ><generator uri="https://jekyllrb.com/" version="3.10.0">Jekyll</generator><link href="https://tsendsuren.github.io/feed.xml" rel="self" type="application/atom+xml" /><link href="https://tsendsuren.github.io/" rel="alternate" type="text/html" /><updated>2025-10-25T18:39:12-07:00</updated><id>https://tsendsuren.github.io/feed.xml</id><title type="html">Personal Wiki</title><subtitle>personal description</subtitle><author><name>Tsendsuren Khurelbaatar</name><email>t.khurelbaatar@griffith.edu.au</email></author><entry><title type="html">Atomic units and handy formulas</title><link href="https://tsendsuren.github.io/posts/2024-06-03-au_conversion/" rel="alternate" type="text/html" title="Atomic units and handy formulas" /><published>2024-06-04T00:00:00-07:00</published><updated>2024-06-04T00:00:00-07:00</updated><id>https://tsendsuren.github.io/posts/au_conversion</id><content type="html" xml:base="https://tsendsuren.github.io/posts/2024-06-03-au_conversion/"><![CDATA[<h1 id="atomic-units">Atomic units</h1>
<h3 id="laser-intensity-conversion">Laser intensity conversion</h3>

<div class="language-python highlighter-rouge"><div class="highlight"><pre class="highlight"><code><span class="n">Intensity</span> <span class="p">[</span><span class="n">au</span><span class="p">]</span> <span class="o">=</span> <span class="n">Intensity</span> <span class="p">[</span><span class="n">W</span><span class="p">.</span><span class="n">cm2</span><span class="p">]</span> <span class="o">/</span> <span class="mf">3.51e16</span> 
</code></pre></div></div>

<h3 id="electric-field-strength">Electric field strength</h3>
<div class="language-python highlighter-rouge"><div class="highlight"><pre class="highlight"><code><span class="n">E</span> <span class="p">[</span><span class="n">au</span><span class="p">]</span> <span class="o">=</span> <span class="n">E</span> <span class="p">[</span><span class="n">V</span><span class="o">/</span><span class="n">m</span><span class="p">]</span> <span class="o">/</span> <span class="mf">5.14e11</span>
</code></pre></div></div>

<h3 id="energy-conversion">Energy conversion</h3>
<div class="language-python highlighter-rouge"><div class="highlight"><pre class="highlight"><code><span class="n">Energy</span> <span class="p">[</span><span class="n">au</span><span class="p">]</span> <span class="o">=</span> <span class="n">Energy</span> <span class="p">[</span><span class="n">eV</span><span class="p">]</span> <span class="o">/</span> <span class="mf">27.21</span>
</code></pre></div></div>

<h3 id="time-conversion">Time conversion</h3>
<div class="language-python highlighter-rouge"><div class="highlight"><pre class="highlight"><code><span class="n">t</span> <span class="p">[</span><span class="n">au</span><span class="p">]</span> <span class="o">=</span> <span class="n">t</span> <span class="p">[</span><span class="n">fs</span><span class="p">]</span> <span class="o">*</span> <span class="mi">1000</span> <span class="o">/</span> <span class="mf">24.2</span>
</code></pre></div></div>

<h3 id="wavelength-conversion">Wavelength conversion</h3>
<div class="language-python highlighter-rouge"><div class="highlight"><pre class="highlight"><code><span class="k">lambda</span> <span class="p">[</span><span class="n">au</span><span class="p">]</span> <span class="o">=</span> <span class="k">lambda</span> <span class="p">[</span><span class="n">nm</span><span class="p">]</span> <span class="o">*</span> <span class="mf">18.89</span>
</code></pre></div></div>

<h3 id="angular-frequency">Angular frequency</h3>
<div class="language-python highlighter-rouge"><div class="highlight"><pre class="highlight"><code><span class="n">omega</span> <span class="p">[</span><span class="n">au</span><span class="p">]</span> <span class="o">=</span> <span class="mf">45.56</span> <span class="o">/</span> <span class="k">lambda</span> <span class="p">[</span><span class="n">nm</span><span class="p">]</span>
</code></pre></div></div>

<h1 id="useful-formulas-in-ultrafast-physics">Useful formulas in ultrafast physics</h1>

<h3 id="wavelength-energy-conversion">Wavelength-energy conversion</h3>

\[E [\mathrm{eV}] = \frac{1240}{\lambda [\mathrm{nm}]}\]

<h3 id="ponderomotive-energy">Ponderomotive energy</h3>

\[U_{p}=\frac{I}{4\omega^{2}}\]]]></content><author><name>Tsendsuren Khurelbaatar</name><email>t.khurelbaatar@griffith.edu.au</email></author><summary type="html"><![CDATA[Atomic units Laser intensity conversion]]></summary></entry><entry><title type="html">Running HR4000 Spectrometer with Python</title><link href="https://tsendsuren.github.io/posts/2024-06-03-OceanOptics/" rel="alternate" type="text/html" title="Running HR4000 Spectrometer with Python" /><published>2024-06-03T00:00:00-07:00</published><updated>2024-06-03T00:00:00-07:00</updated><id>https://tsendsuren.github.io/posts/OceanOptics</id><content type="html" xml:base="https://tsendsuren.github.io/posts/2024-06-03-OceanOptics/"><![CDATA[<h1 id="intro">Intro</h1>
<p>Ocean Optics spectrometers are a staple in many laser labs, known for their high quality. However, their reliance on proprietary software and drivers can be cumbersome. Fortunately, Python offers a flexible and customizable alternative for controlling these devices and acquiring spectrum data.</p>

<p>With a simple Python script, you can bypass the need for Ocean Optics’ software and drivers, and directly interface with your spectrometer. This approach streamlines your workflow and empowers you to tailor the data collection process to your specific experimental needs.</p>

<p>In my own research, I wrote a simple Python code snippet that seamlessly connects to the Ocean Optics HR4000 spectrometer and retrieves spectral readouts. By incorporating this code into your experiments, you can unlock a more efficient and adaptable way to work with your spectrometer.</p>

<h2 id="getting-started">Getting Started</h2>

<p>Before you can use this program to interact with your OceanOptics HR4000 spectrometer, you’ll need to install the <code class="language-plaintext highlighter-rouge">python-seabreeze</code> library. This library serves as a bridge between the spectrometer hardware and your Python code, enabling seamless communication and data retrieval.</p>

<h3 id="installation">Installation</h3>

<ol>
  <li>
    <p><strong>Install <code class="language-plaintext highlighter-rouge">python-seabreeze</code></strong>:</p>

    <p>To get started, you can install <code class="language-plaintext highlighter-rouge">python-seabreeze</code> using the following pip command:</p>

    <p>```bash
pip install seabreeze</p>
  </li>
</ol>

<p>Refer to the python-seabreeze documentation for more detailed installation instructions and to ensure compatibility with your operating system.</p>

<h3 id="using-the-program">Using the Program</h3>
<p>Once you’ve successfully installed python-seabreeze, you can run the program to connect with your OceanOptics HR4000 spectrometer.</p>

<h3 id="live-spectrum-display">Live Spectrum Display</h3>
<p>As you work with your OceanOptics HR4000 spectrometer, the program will continuously retrieve and display the real-time spectral data. This live spectrum display makes it incredibly convenient to monitor and analyze your data as you work with your setup.</p>

<div class="language-python highlighter-rouge"><div class="highlight"><pre class="highlight"><code><span class="kn">import</span> <span class="nn">matplotlib.pyplot</span> <span class="k">as</span> <span class="n">plt</span>
<span class="kn">import</span> <span class="nn">numpy</span> <span class="k">as</span> <span class="n">np</span>
<span class="kn">import</span> <span class="nn">time</span>
<span class="kn">from</span> <span class="nn">seabreeze.spectrometers</span> <span class="kn">import</span> <span class="n">Spectrometer</span><span class="p">,</span> <span class="n">list_devices</span>

<span class="n">devices</span> <span class="o">=</span> <span class="n">list_devices</span><span class="p">()</span>
<span class="k">print</span><span class="p">(</span><span class="n">devices</span><span class="p">)</span>
<span class="n">spec</span> <span class="o">=</span> <span class="n">Spectrometer</span><span class="p">(</span><span class="n">devices</span><span class="p">[</span><span class="mi">0</span><span class="p">])</span>

<span class="c1"># Set integration time if needed
</span><span class="n">int_time</span> <span class="o">=</span> <span class="n">spec</span><span class="p">.</span><span class="n">integration_time_micros</span><span class="p">(</span><span class="mi">10000</span><span class="p">)</span>

<span class="n">wavelengths</span> <span class="o">=</span> <span class="n">spec</span><span class="p">.</span><span class="n">wavelengths</span><span class="p">()</span>
<span class="n">intensities</span> <span class="o">=</span> <span class="n">spec</span><span class="p">.</span><span class="n">intensities</span><span class="p">()</span>

<span class="c1"># data = np.column_stack((wavelengths, intensities))
# fname = "bg_spectrum.txt"
# np.savetxt(fname, data, delimiter='\t')
</span>
<span class="c1"># bg_data = np.loadtxt('bg_spectrum.txt')
# bg_signal = bg_data[:,1]
</span>
<span class="n">fig</span><span class="p">,</span> <span class="n">ax</span> <span class="o">=</span> <span class="n">plt</span><span class="p">.</span><span class="n">subplots</span><span class="p">()</span>
<span class="k">while</span> <span class="bp">True</span><span class="p">:</span>
    <span class="n">intensities</span> <span class="o">=</span> <span class="n">spec</span><span class="p">.</span><span class="n">intensities</span><span class="p">()</span>
    <span class="c1"># intensities = intensities-bg_signal
</span>    <span class="n">ax</span><span class="p">.</span><span class="n">clear</span><span class="p">()</span>
    <span class="n">ax</span><span class="p">.</span><span class="n">plot</span><span class="p">(</span><span class="n">wavelengths</span><span class="p">,</span><span class="n">intensities</span><span class="p">,</span><span class="s">'r'</span><span class="p">)</span>
    <span class="n">ax</span><span class="p">.</span><span class="n">set_xlabel</span><span class="p">(</span><span class="s">'Wavelength (nm)'</span><span class="p">)</span>
    <span class="n">ax</span><span class="p">.</span><span class="n">set_ylabel</span><span class="p">(</span><span class="s">'Intensity (arb.unit)'</span><span class="p">)</span>
    <span class="n">ax</span><span class="p">.</span><span class="n">set_xlim</span><span class="p">(</span><span class="mi">200</span><span class="p">,</span><span class="mi">1100</span><span class="p">)</span>
    <span class="c1"># ax.set_ylim(0,7000)
</span>    <span class="n">plt</span><span class="p">.</span><span class="n">grid</span><span class="p">()</span>
    <span class="n">plt</span><span class="p">.</span><span class="n">pause</span><span class="p">(</span><span class="mf">0.1</span><span class="p">)</span>
    
    <span class="k">if</span> <span class="n">plt</span><span class="p">.</span><span class="n">waitforbuttonpress</span><span class="p">(</span><span class="n">timeout</span><span class="o">=</span><span class="mf">0.1</span><span class="p">):</span>
        <span class="k">break</span>

<span class="n">plt</span><span class="p">.</span><span class="n">show</span><span class="p">()</span>
</code></pre></div></div>]]></content><author><name>Tsendsuren Khurelbaatar</name><email>t.khurelbaatar@griffith.edu.au</email></author><summary type="html"><![CDATA[Intro Ocean Optics spectrometers are a staple in many laser labs, known for their high quality. However, their reliance on proprietary software and drivers can be cumbersome. Fortunately, Python offers a flexible and customizable alternative for controlling these devices and acquiring spectrum data.]]></summary></entry><entry><title type="html">My PhD Dissertation: Exploring Attosecond Chemical Physics</title><link href="https://tsendsuren.github.io/posts/2024-05-26-PhD-dissertation/" rel="alternate" type="text/html" title="My PhD Dissertation: Exploring Attosecond Chemical Physics" /><published>2024-05-26T00:00:00-07:00</published><updated>2024-05-26T00:00:00-07:00</updated><id>https://tsendsuren.github.io/posts/PhD-dissertation</id><content type="html" xml:base="https://tsendsuren.github.io/posts/2024-05-26-PhD-dissertation/"><![CDATA[<p>Throughout my PhD journey (2014-2021), I’ve had the incredible opportunity to delve into the captivating field of attosecond physics (\(10^{-18}\) sec). Based at the Max Planck Center for Attosecond Science, as part of the Max Planck/POSTECH Korea initiative, my focus has been on developing an attosecond beamline with a specific goal in mind: measuring attosecond charge migration in biologically relevant molecules.</p>

<p>Utilizing ultrashort deep-UV and attosecond XUV pulses, I’ve been on a quest to unravel the intricacies of molecular dynamics at the most fundamental level. It’s been an exhilarating journey filled with challenges and discoveries.</p>

<p>If you’re keen to learn more about my research and the fascinating world of attosecond chemical physics, I invite you to explore my full dissertation:</p>

<p><a href="http://tsendsuren.github.io/files/Tsendsuren_Dissertation.pdf">Download Dissertation</a></p>]]></content><author><name>Tsendsuren Khurelbaatar</name><email>t.khurelbaatar@griffith.edu.au</email></author><summary type="html"><![CDATA[Throughout my PhD journey (2014-2021), I’ve had the incredible opportunity to delve into the captivating field of attosecond physics (\(10^{-18}\) sec). Based at the Max Planck Center for Attosecond Science, as part of the Max Planck/POSTECH Korea initiative, my focus has been on developing an attosecond beamline with a specific goal in mind: measuring attosecond charge migration in biologically relevant molecules.]]></summary></entry><entry><title type="html">Магистрын дипломын ажил</title><link href="https://tsendsuren.github.io/posts/2024-05-24-MSc-Thesis/" rel="alternate" type="text/html" title="Магистрын дипломын ажил" /><published>2024-05-24T00:00:00-07:00</published><updated>2024-05-24T00:00:00-07:00</updated><id>https://tsendsuren.github.io/posts/MSc-Thesis</id><content type="html" xml:base="https://tsendsuren.github.io/posts/2024-05-24-MSc-Thesis/"><![CDATA[<p>Энэхүү магистрийн дипломын ажлыг 2012 онд МУИС-ын Физик электроникын сургуулийн Физикийн тэнхимд Проф. Ц.Ганцог багшийн удирдлага доор хийж байсан болно.</p>

<p><a href="http://tsendsuren.github.io/files/Tsendsuren_MScThesis.pdf">Download PDF</a></p>]]></content><author><name>Tsendsuren Khurelbaatar</name><email>t.khurelbaatar@griffith.edu.au</email></author><summary type="html"><![CDATA[Энэхүү магистрийн дипломын ажлыг 2012 онд МУИС-ын Физик электроникын сургуулийн Физикийн тэнхимд Проф. Ц.Ганцог багшийн удирдлага доор хийж байсан болно.]]></summary></entry></feed>