# Technical Document Extraction: Heatmap Analysis of K₂ with Varying E_F
## Image Overview
The image contains two side-by-side heatmaps labeled **(f)** and **(h)**, depicting streamline flow patterns in a 2D spatial domain. Both panels share identical axis labels and color scales but differ in the sign of the Fermi energy parameter **E_F**.
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### **Panel (f): K₂ with E_F = +0.035t**
#### Labels and Axis Titles
- **X-axis**: `length (nm)` ranging from -40 nm to 40 nm.
- **Y-axis**: `width (nm)` ranging from -10 nm to 10 nm.
- **Title**: `(f) K₂: E_F=+0.035t`
- **Color Bar**:
- **Range**: 0.0 (white) to 0.4 (red).
- **Position**: Right of the panel.
- **Spatial Grounding**: Legend located at `[x=45 nm, y=-10 nm]` (relative to the heatmap's coordinate system).
#### Components and Flow
- **Streamlines**: Blue arrows indicate vector direction and magnitude.
- **Color Gradient**:
- **High Intensity (Red)**: Central region (x ≈ 0 nm, y ≈ 0 nm).
- **Low Intensity (White)**: Edges (x ≈ ±40 nm, y ≈ ±10 nm).
- **Trend Verification**:
- Arrows in the central region point outward radially, with density decreasing toward the edges.
- Color intensity peaks at the center (red) and diminishes toward the edges (white).
---
### **Panel (h): K₂ with E_F = -0.035t**
#### Labels and Axis Titles
- **X-axis**: `length (nm)` ranging from -40 nm to 40 nm.
- **Y-axis**: `width (nm)` ranging from -10 nm to 10 nm.
- **Title**: `(h) K₂: E_F=-0.035t`
- **Color Bar**:
- **Range**: 0.0 (white) to 0.4 (red).
- **Position**: Right of the panel.
- **Spatial Grounding**: Legend located at `[x=45 nm, y=-10 nm]`.
#### Components and Flow
- **Streamlines**: Blue arrows indicate vector direction and magnitude.
- **Color Gradient**:
- **Low Intensity (White)**: Central region (x ≈ 0 nm, y ≈ 0 nm).
- **High Intensity (Red)**: Edges (x ≈ ±40 nm, y ≈ ±10 nm).
- **Trend Verification**:
- Arrows in the central region point inward radially, with density increasing toward the edges.
- Color intensity peaks at the edges (red) and diminishes toward the center (white).
---
### Key Observations
1. **Symmetry**: Both panels exhibit bilateral symmetry about the x=0 nm axis.
2. **E_F Dependency**:
- Positive **E_F** (+0.035t) in (f) correlates with outward flow and central intensity.
- Negative **E_F** (-0.035t) in (h) correlates with inward flow and edge intensity.
3. **Legend Consistency**:
- Red (0.4) and white (0.0) values match the intensity peaks in both panels.
- Arrows align with the gradient direction (e.g., outward flow in red regions of (f)).
---
### Notes
- **Language**: All text is in English.
- **Data Extraction**: No numerical tables or embedded text beyond axis labels and titles.
- **Missing Information**: No explicit units for **t** (likely a material constant, e.g., thickness or temperature).
